Minute to Hour Converter
Convert minutes to hours with our free online time converter.
Quick Answer
1 Minute = 0.016667 hours
Formula: Minute × conversion factor = Hour
Use the calculator below for instant, accurate conversions.
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All conversion formulas on UnitsConverter.io have been verified against NIST (National Institute of Standards and Technology) guidelines and international SI standards. Our calculations are accurate to 10 decimal places for standard conversions and use arbitrary precision arithmetic for astronomical units.
Minute to Hour Calculator
How to Use the Minute to Hour Calculator:
- Enter the value you want to convert in the 'From' field (Minute).
- The converted value in Hour will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Time category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Minute to Hour: Step-by-Step Guide
Converting Minute to Hour involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Minute = 0.0166667 hoursExample Calculation:
Convert 60 minutes: 60 × 0.0166667 = 1 hours
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
Need to convert to other time units?
View all Time conversions →What is a Minute and a Hour?
The minute (symbol: min) is a unit of time equal to 60 seconds or 1/60 of an hour (exactly 0.016̄ hours, or approximately 0.0167 hours).
Official SI-derived definition: Since the second was redefined atomically in 1967, one minute equals exactly 60 seconds, where each second is the duration of 9,192,631,770 periods of radiation from caesium-133 atoms. Therefore:
- 1 minute = 60 × 9,192,631,770 = 551,558,906,200 caesium-133 oscillations
Practical conversions:
- 1 minute = 60 seconds (exact)
- 1 minute = 0.016666... hours (1/60 hr, exact)
- 1 hour = 60 minutes (exact)
- 1 day = 1,440 minutes (24 × 60)
- 1 week = 10,080 minutes (7 × 24 × 60)
- 1 year (365 days) = 525,600 minutes (memorably featured in the musical Rent)
The minute is not an SI base unit, but it is accepted for use with the SI alongside hours, days, and other traditional time units due to its universal cultural importance and practical utility.
Why 60?
The choice of 60 comes from ancient Babylonian sexagesimal (base-60) mathematics, developed around 3000 BCE. The Babylonians chose 60 because it's highly divisible:
- Factors of 60: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60 (12 factors!)
- This makes fractions like 1/2 (30 min), 1/3 (20 min), 1/4 (15 min), 1/5 (12 min), 1/6 (10 min) all whole numbers
- Contrast with decimal: 100 only has factors 1, 2, 4, 5, 10, 20, 25, 50, 100 (9 factors, and divisions like 1/3 = 33.33...)
This mathematical convenience made base-60 ideal for astronomy, geometry, and timekeeping—fields requiring frequent division. The system persists today in our 60-minute hours, 60-second minutes, and 360-degree circles (6 × 60).
The hour (symbol: h or hr) is a unit of time equal to 60 minutes, 3,600 seconds, or 1/24 of a day.
Official SI-derived definition: Since the second was redefined atomically in 1967, one hour equals exactly 3,600 seconds, where each second is 9,192,631,770 periods of caesium-133 radiation. Therefore:
- 1 hour = 3,600 × 9,192,631,770 = 33,074,688,259,200,000 caesium-133 oscillations
- This equals approximately 33.07 quadrillion atomic oscillations
Practical conversions:
- 1 hour = 60 minutes (exact)
- 1 hour = 3,600 seconds (exact)
- 1 day = 24 hours (exact)
- 1 week = 168 hours (7 × 24)
- 1 year (365 days) = 8,760 hours (365 × 24)
The hour is not an SI base unit, but it is accepted for use with the SI due to its fundamental role in civil timekeeping and global coordination.
The 24-Hour Day
The division of the day into 24 hours reflects both astronomical reality and historical convention:
Astronomical basis:
- Earth rotates 360° in ~24 hours (one solar day)
- Each hour = 15° of rotation (360° ÷ 24 = 15°)
- This is why time zones are spaced ~15° longitude apart
- Solar noon occurs when the sun crosses the meridian (highest point)
Why 24, not 20 or 10?
- Ancient Egyptians used base-12 counting (duodecimal)
- 12 is highly divisible: factors are 1, 2, 3, 4, 6, 12
- 12 daytime hours + 12 nighttime hours = 24-hour cycle
- This system was inherited by Greeks, Romans, and eventually globally standardized
Solar vs. Sidereal Hours:
- Solar hour: Based on Earth's rotation relative to the Sun (24 hours per cycle)
- Sidereal hour: Based on Earth's rotation relative to distant stars (23 hours, 56 minutes, 4 seconds per cycle)
- Civil timekeeping uses solar hours because they align with day/night cycles
Note: The Minute is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Hour belongs to the imperial/US customary system.
History of the Minute and Hour
of the Minute
Ancient Babylonian Origins (c. 3000 BCE)
The foundation of the minute lies in the Sumerian and Babylonian sexagesimal (base-60) number system developed in ancient Mesopotamia around 3000 BCE. The Babylonians used this system for:
- Astronomical calculations: Dividing the celestial sphere and tracking planetary movements
- Geometric measurements: Dividing circles into 360 degrees (6 × 60)
- Mathematical computations: Facilitating complex fractions and divisions
- Calendar systems: Organizing time into convenient subdivisions
Cuneiform tablets from this era show sophisticated astronomical observations recorded using base-60 divisions, laying groundwork for the eventual minute.
Greek Astronomical Adoption (150 CE)
The ancient Greeks, particularly Claudius Ptolemy (c. 100-170 CE), formalized the division of hours and degrees into 60 parts in his astronomical treatise Almagest. Ptolemy used Latin terminology inherited from earlier traditions:
- "pars minuta prima" (first minute/small part) = 1/60 of a degree or hour → modern minute
- "pars minuta secunda" (second minute/small part) = 1/60 of a minute = 1/3600 of a degree/hour → modern second
These terms were primarily used for angular measurement in astronomy and navigation (describing positions of stars and planets), not yet for practical daily timekeeping.
Medieval Islamic and European Transmission (800-1300 CE)
During the Islamic Golden Age (8th-13th centuries), Arab astronomers and mathematicians preserved and expanded on Greek astronomical texts, continuing to use the 60-part division system.
When European scholars translated Arabic astronomical manuscripts in the 12th and 13th centuries (particularly at translation centers in Toledo, Spain, and Sicily), they reintroduced the Latin terms "pars minuta prima" and "pars minuta secunda" to European scholarship.
However, these remained primarily theoretical and astronomical units. Practical timekeeping in medieval Europe relied on:
- Sundials (showing hours)
- Water clocks (clepsydrae)
- Candle clocks (burning time)
- Church bells marking canonical hours (Matins, Prime, Terce, Sext, None, Vespers, Compline)
None of these devices tracked minutes—they were too imprecise, and daily life didn't require such granularity.
Mechanical Clocks Emerge—But No Minute Hands (1300s)
The first mechanical clocks appeared in Europe around 1280-1300, installed in church towers and public buildings. Early examples include:
- Salisbury Cathedral clock (England, c. 1386) - still running, one of the oldest working clocks
- Wells Cathedral clock (England, c. 1390)
- Prague Astronomical Clock (Czech Republic, 1410)
Crucially, these early clocks had only an HOUR hand. They were too inaccurate (losing or gaining 15-30 minutes per day) to justify displaying minutes. The concept of "being on time" to the minute was essentially meaningless when clocks could drift that much daily.
Pendulum Revolution: Minutes Become Meaningful (1656)
The transformative moment for minute-level timekeeping came with Christiaan Huygens' invention of the pendulum clock in 1656. This invention improved timekeeping accuracy from errors of 15 minutes per day to less than 15 seconds per day—a roughly 60-fold improvement.
Why pendulums revolutionized accuracy:
- A pendulum's swing period depends only on its length and gravity (Galileo's discovery, 1602)
- Length is constant → period is constant → highly regular "tick"
- Formula: Period = 2π√(L/g), where L = length, g = gravitational acceleration
- A 1-meter pendulum has a period of approximately 2 seconds—perfect for timekeeping
With this accuracy, displaying minutes became both practical and necessary. Clockmakers began adding minute hands to clock faces around 1660-1680.
Minute Hands Become Standard (1670-1750)
By the late 17th century:
- 1670s: Quality clocks routinely featured minute hands
- 1680s: Balance spring invention (Huygens and Robert Hooke) further improved accuracy, enabling portable watches to track minutes
- 1700s: Minute display became universal on both public clocks and personal timepieces
- 1761: John Harrison's H4 marine chronometer achieved extraordinary accuracy (losing only 5 seconds on a 81-day voyage), revolutionizing navigation
The minute transformed from an astronomical abstraction to a practical daily measurement, changing social organization fundamentally.
Societal Impact: The "Minute Culture" (1800s)
The 19th century saw the rise of minute-precise scheduling, driven by:
-
Railroad timetables (1840s onward):
- Trains required synchronized schedules to prevent collisions
- Railway time standardized clocks across regions
- Timetables specified arrivals/departures to the minute
- This drove development of time zones and standard time
-
Factory work and "time discipline" (Industrial Revolution):
- Factory shifts started at precise times (e.g., 7:00 AM, not "dawn")
- Workers punched time clocks tracking arrival to the minute
- The concept of "being late" became economically significant
- Frederick Winslow Taylor's "scientific management" (1880s-1910s) measured work tasks in minutes and seconds
-
Urban life coordination:
- Meeting times specified to the minute
- Public transportation schedules
- School bell systems marking class periods
This represented a profound cultural shift: pre-industrial societies organized time around seasonal cycles, sunlight, and approximate "hours." Industrial society required minute-level coordination of human activity.
Atomic Age: Minutes Defined by Seconds (1967-Present)
When the second was redefined in 1967 based on caesium-133 atomic oscillations (9,192,631,770 cycles = 1 second), the minute automatically inherited this precision:
1 minute = exactly 60 × 9,192,631,770 caesium oscillations = 551,558,906,200 caesium oscillations
Modern atomic clocks maintain this definition with extraordinary stability, losing less than 1 second in 100 million years. This means the minute is now defined with sub-nanosecond precision, far beyond any practical human need but essential for:
- GPS systems (requiring nanosecond synchronization)
- Financial trading (high-frequency trading in microseconds)
- Telecommunications (network synchronization)
- Scientific experiments (particle physics, gravitational wave detection)
The "525,600 Minutes" Cultural Moment (1996)
In 1996, the musical Rent by Jonathan Larson opened on Broadway, featuring the iconic song "Seasons of Love," which begins:
"Five hundred twenty-five thousand, six hundred minutes... How do you measure, measure a year?"
This number—525,600 minutes = 365 days × 24 hours × 60 minutes—became a cultural touchstone, highlighting the minute as a unit for measuring the passage of life itself, not just scheduling appointments.
of the Hour
Ancient Egyptian Origins (c. 2000 BCE)
The earliest systematic division of day and night into hours comes from ancient Egypt around 2000 BCE. Egyptian priests needed to schedule temple rituals and religious observations throughout the day and night.
Egyptian timekeeping innovations:
-
Shadow clocks (sundials): Used during daylight to track time by shadow position
- Divided daylight into 12 parts
- Earliest example: Obelisk shadow clock (c. 1500 BCE)
-
Water clocks (clepsydrae): Used at night and cloudy days
- Water dripped from container at constant rate
- Markings indicated elapsed time
- Divided nighttime into 12 parts
Crucial limitation: Seasonal hours (temporales horae)
- Summer daylight hours were longer than winter daylight hours
- Example: In Egypt, summer daytime hour ≈ 75 minutes, winter daytime hour ≈ 45 minutes
- Nighttime hours varied inversely (longer in winter, shorter in summer)
- This made sense for agricultural societies organized around daylight availability
Why 12 divisions?
- Egyptians used base-12 (duodecimal) counting, possibly because:
- 12 lunar months per year
- 12 knuckles on four fingers (excluding thumb)—convenient finger counting
- 12 is highly divisible (1, 2, 3, 4, 6, 12)
Greek and Roman Refinement (300 BCE - 400 CE)
Hellenistic astronomers (c. 300 BCE) introduced the concept of equal-length hours:
- "Equinoctial hours": Dividing the full 24-hour day-night cycle into 24 equal parts
- Each equinoctial hour = 1/24 of a mean solar day
- This was primarily used for astronomical calculations, not daily timekeeping
- Hipparchus (c. 150 BCE) used equinoctial hours for celestial observations
Roman timekeeping:
- Romans continued using seasonal hours for daily life
- Day (from sunrise to sunset) divided into 12 horae
- Night divided into 4 vigiliae (watches) of 3 hours each
- "First hour" (prima hora) = first hour after sunrise (varies by season)
- "Sixth hour" (sexta hora) = midday → origin of "siesta"
- "Eleventh hour" = last hour before sunset → modern idiom "at the eleventh hour" (last minute)
Roman water clocks (clepsydrae):
- Public water clocks in marketplaces
- Adjusted seasonally to maintain 12-hour daytime divisions
- Used for timing speeches in Senate (each senator allotted specific time)
Medieval Islamic Golden Age (700-1300 CE)
Islamic scholars made critical advances in precise timekeeping for astronomical observations and prayer time calculations:
Five daily prayers (salat):
- Fajr (dawn), Dhuhr (midday), Asr (afternoon), Maghrib (sunset), Isha (evening)
- Required accurate determination of solar positions
- Drove development of sophisticated astronomical clocks
Key innovations:
- Astronomical tables (zij): Calculated prayer times using equinoctial hours
- Astrolabes: Portable astronomical computers for time determination
- Advanced water clocks: Al-Jazari's "Castle Clock" (1206) featured complex automata
- Mathematical timekeeping: Used trigonometry to calculate hour angles
Islamic astronomers fully adopted equinoctial hours for scientific work while society continued using seasonal hours for daily activities.
Mechanical Clocks and Hour Standardization (1300-1600)
The invention of mechanical clocks in medieval Europe around 1280-1300 CE forced the adoption of equal-length hours:
Why mechanical clocks standardized hours:
- Mechanical escapement mechanisms tick at constant rates
- Cannot automatically adjust for seasonal variations
- Fixed 24-hour cycle physically built into clockwork
- This made equal-length hours the practical default
Early public clocks:
- Salisbury Cathedral Clock (England, c. 1386): Still running, one of oldest
- Wells Cathedral Clock (England, c. 1390): Features astronomical dial
- Prague Astronomical Clock (Czech Republic, 1410): Shows multiple time systems
- Church tower clocks visible/audible across towns
- Bells chimed on the hour, coordinating community activities
Impact on society:
- Transition from "task-oriented time" (work until task done) to "clock time" (work specific hours)
- Monasteries first adopted strict hour-based schedules (canonical hours)
- Urban merchants and craftsmen followed
- "Time discipline" emerged: punctuality became valued
Hour angles and navigation:
- 1 hour = 15° longitude (since Earth rotates 360° in 24 hours)
- Ships could determine longitude by comparing local solar noon to chronometer showing home port time
- This principle drove development of marine chronometers in 1700s
12-Hour vs. 24-Hour Time Notation
12-hour clock (with AM/PM):
- AM = ante meridiem (Latin: before midday)
- PM = post meridiem (Latin: after midday)
- Hours: 12:00 AM (midnight), 1 AM-11 AM, 12:00 PM (noon), 1 PM-11 PM
- Used in: United States, Canada, Australia, Philippines, parts of Latin America
- Ambiguity issue: 12:00 AM vs. 12:00 PM frequently confused
24-hour clock (military time):
- Hours numbered 00:00 (midnight) through 23:59
- Used in: Most of Europe, Asia, Africa, South America, military/aviation worldwide
- ISO 8601 international standard: HH:MM:SS format (e.g., 14:30:00)
- Eliminates AM/PM ambiguity
- Preferred for timetables, logistics, computing
Historical development:
- Ancient Egyptians and Romans used 1-12 numbering twice daily
- 24-hour notation emerged with astronomical use in Renaissance
- Military adoption (especially WWI era) standardized 24-hour format
- Computing systems use 24-hour format internally
Time Zones: Dividing Earth into Hours (1883-1884)
Before the late 1800s, each town kept its own "local solar time" based on the sun's position. This created chaos for railroad timetables—a train journey might cross dozens of different local times.
Railroad time standardization (1883):
- US/Canadian railroads established four continental time zones on November 18, 1883
- Each zone spanned roughly 15° longitude (one hour)
- Cities synchronized clocks within each zone
International Meridian Conference (1884, Washington D.C.):
- Established Greenwich, England as 0° longitude (Prime Meridian)
- Divided Earth into 24 standard time zones, each 15° wide
- Each zone offset by one hour from UTC (Coordinated Universal Time, formerly GMT)
- Created International Date Line at 180° longitude
Modern time zones:
- Standard zones: UTC-12 to UTC+14 (some zones offset by 30 or 45 minutes)
- Daylight Saving Time: Advances clocks 1 hour in summer in some regions
- Political boundaries: Zones follow country borders, not just longitude
- China uses single time zone (UTC+8) despite spanning 5 geographical zones
Atomic Era: Hours Defined by Seconds (1967-Present)
When the second was redefined atomically in 1967 based on caesium-133 oscillations, the hour inherited this precision:
1 hour = exactly 3,600 SI seconds = 33,074,688,259,200,000 caesium oscillations
Modern atomic clocks maintain this definition with extraordinary stability:
- Caesium fountain clocks: Accurate to 1 second in 100 million years
- Optical lattice clocks: Accurate to 1 second in 15 billion years (2019)
- GPS satellites: Each carries atomic clocks synchronized to nanoseconds
Leap seconds:
- Earth's rotation gradually slows (tidal friction)
- Occasionally, an extra second added to clock time to match Earth rotation
- 27 leap seconds added 1972-2016
- Controversy: May be abolished in favor of "leap hours" every few centuries
Common Uses and Applications: minutes vs hours
Explore the typical applications for both Minute (imperial/US) and Hour (imperial/US) to understand their common contexts.
Common Uses for minutes
and Applications
1. Time Management and Productivity
The minute is the fundamental unit for personal and professional time management:
- Pomodoro Technique: Work in 25-minute focused sessions, followed by 5-minute breaks
- Time blocking: Schedule day in 15-, 30-, or 60-minute blocks
- Task estimation: "This report will take 45 minutes"
- Billable hours: Professional services (lawyers, consultants) often bill in 6-minute increments (0.1 hour)
- Timesheet tracking: Many systems track work time to the minute
Digital tools: Calendar apps (Google Calendar, Outlook), time tracking software (Toggl, RescueTime), and project management platforms (Asana, Monday.com) all operate on minute-based scheduling.
2. Scheduling and Appointments
Minutes enable precise coordination of activities:
- Appointment times: "Dentist at 3:15 PM" (hours and minutes)
- Event start times: "Meeting begins at 10:30 AM sharp"
- Transit timetables: "Train departs at 8:47 AM"
- Reservation systems: OpenTable shows "5:30 PM" or "8:45 PM" slots
- Class schedules: "Period 3: 10:25-11:15 AM" (50-minute period)
Buffer times: Professional schedulers often include 5-10 minute buffers between appointments to prevent domino-effect delays.
3. Sports and Athletic Competition
Many sports use minutes for game structure and performance measurement:
-
Game periods:
- Soccer: Two 45-minute halves
- Basketball (NBA): Four 12-minute quarters = 48 minutes total
- Basketball (NCAA): Two 20-minute halves = 40 minutes
- Hockey: Three 20-minute periods
- Rugby: Two 40-minute halves
-
Penalties and suspensions:
- Hockey penalty box: 2-minute, 4-minute, or 5-minute penalties
- Soccer yellow card: 10-minute sin bin (trial rule in some leagues)
-
Running performance:
- Mile time: 4-6 minutes (recreational), under 4 minutes (elite)
- 5K time: 15-30 minutes (recreational), 13-15 minutes (competitive)
- Marathon pace: Expressed as minutes per mile/km
-
Timeouts:
- NBA timeout: 75 seconds (1.25 minutes) or 30 seconds
- NFL timeout: Each team gets three per half
- College football: 1-minute timeouts
4. Navigation and Geography
Beyond time measurement, "minute" has a distinct meaning in navigation:
Arcminute (minute of arc):
- Symbol: ′ (prime symbol)
- 1 arcminute = 1/60 of a degree of angle
- 1 degree = 60 arcminutes = 60′
- 1 arcminute = 60 arcseconds = 60″
Latitude and longitude:
- Geographic coordinates: 40°45′30″N, 73°59′00″W (New York City)
- Reads as: "40 degrees, 45 minutes, 30 seconds North; 73 degrees, 59 minutes, 0 seconds West"
Nautical mile:
- 1 nautical mile = 1 arcminute of latitude (approximately 1,852 meters)
- This makes ocean navigation calculations elegant: traveling 60 nautical miles north changes your latitude by 1 degree
Map precision:
- 1 arcminute of latitude ≈ 1.85 km (1.15 miles)
- 1 arcminute of longitude ≈ 1.85 km at equator (decreases toward poles)
- Modern GPS coordinates often express minutes with decimal precision: 40°45.5′N
5. Digital Timekeeping and Computing
Computers and digital devices track time in minutes (and smaller units):
- System clocks: Display hours:minutes (14:35) or hours:minutes:seconds (14:35:47)
- File timestamps: Modified time recorded as YYYY-MM-DD HH:MM:SS
- Cron jobs: Unix/Linux scheduled tasks use minute-level specification (0-59)
- Session timeouts: "Session will expire in 5 minutes of inactivity"
- Auto-save intervals: Microsoft Word auto-saves every 10 minutes (default)
- Video timestamps: YouTube shows 5:23 (5 minutes, 23 seconds)
- Countdown timers: Online cooking timers, exam clocks, auction endings
6. Aviation and Air Travel
The aviation industry relies heavily on minute-precise timing:
- Flight schedules: Departure 10:25 AM, arrival 1:47 PM (all times to the minute)
- Flight duration: "Flight time: 2 hours 34 minutes"
- Boarding times: "Boarding begins 30 minutes before departure"
- Gate changes: "Gate closes 10 minutes before departure"
- Air traffic control: Separation requirements measured in minutes between aircraft
- Fuel planning: Reserve fuel calculated for 30-45 minutes of additional flight time
7. Education and Testing
Academic settings structure learning and assessment by minutes:
-
Class periods:
- Elementary school: 45-60 minute periods
- High school: 50-minute periods (traditional) or 90-minute blocks
- University lecture: 50 minutes ("hour" classes), 80 minutes (longer sessions)
- "10-minute break" between classes
-
Standardized tests:
- SAT Reading section: 65 minutes
- SAT Math (calculator): 55 minutes
- ACT Science: 35 minutes
- GRE Verbal section: 30 minutes
- LSAT Logical Reasoning: 35 minutes per section
-
Test-taking strategy: Students allocate time per question (e.g., "100 questions in 60 minutes = 36 seconds per question")
8. Parking and Paid Time
Many services charge based on minute increments:
-
Parking meters:
- 15-minute minimum in some cities
- $2 per hour = $0.50 per 15 minutes
- Digital meters show minutes remaining
-
Bike/scooter sharing:
- Lime, Bird, Citibike: Charge per minute (e.g., $0.39/min)
- "Unlock fee + per-minute rate"
-
Phone plans (historical):
- Pre-smartphone era: Plans sold as "450 minutes per month"
- Long-distance charges: "5¢ per minute"
- Modern shift: Unlimited minutes, data caps instead
-
Professional services:
- Legal billing: Often in 6-minute increments (1/10 hour)
- Therapy sessions: 50-minute "hour" (allows 10 minutes for notes)
- Consulting rates: "$200/hour" = $3.33/minute
9. Emergency Services
Response time measured in minutes can mean life or death:
-
Response time targets:
- Ambulance (urban): 8 minutes average target
- Fire department: 4-minute turnout time (from alarm to truck departure)
- Police: Varies widely, 5-10 minutes for priority calls
-
Emergency medical guidelines:
- Start CPR within 1 minute of cardiac arrest recognition
- Defibrillation within 3-5 minutes of cardiac arrest improves survival
- Every 1-minute delay in defibrillation decreases survival by 7-10%
- "Time is tissue" in stroke care: Every minute counts
-
911 call processing:
- Average call duration: 2-3 minutes
- Location identification: Should be under 30 seconds
- "Stay on the line" until help arrives
When to Use hours
and Applications
1. Time Zones and Global Coordination
The hour is the basis for global time coordination:
-
UTC (Coordinated Universal Time):
- Global time standard (replaced GMT in 1960s)
- Based on atomic clocks
- All time zones expressed as UTC offset
-
Major time zones:
- EST (Eastern Standard Time): UTC-5
- CST (Central Standard Time): UTC-6
- MST (Mountain Standard Time): UTC-7
- PST (Pacific Standard Time): UTC-8
- GMT/WET (Western European Time): UTC+0
- CET (Central European Time): UTC+1
- IST (Indian Standard Time): UTC+5:30
- JST (Japan Standard Time): UTC+9
- AEST (Australian Eastern Standard Time): UTC+10
-
Business hours across zones:
- "9 AM EST / 6 AM PST" (3-hour difference)
- International meetings: Finding overlapping work hours
- "Follow the sun" support: 24-hour coverage across global offices
-
International Date Line:
- 180° longitude (opposite side of Earth from Prime Meridian)
- Crossing eastward: Lose one day (skip 24 hours forward)
- Crossing westward: Gain one day (repeat 24 hours)
2. Scheduling and Calendar Systems
Hours are the building blocks of schedules:
-
Digital calendars:
- Google Calendar, Outlook: Default 1-hour event blocks
- Day view: Shows 24 hours (or work hours only)
- Week view: 168 hours (7 × 24)
- Buffer time: 15-30 minutes between hour blocks
-
Appointment systems:
- Medical: 15-minute to 1-hour slots
- Salon/spa: 30 minutes to 3 hours
- Professional meetings: 30-minute or 1-hour default
-
Business hours:
- Standard: 9 AM - 5 PM (8 hours, often called "9-to-5")
- Extended: 8 AM - 6 PM (10 hours)
- 24/7 operations: Open all 24 hours, 7 days per week
-
Peak hours vs. off-peak:
- Rush hour: 7-9 AM, 4-7 PM (commute times)
- Electricity pricing: Higher rates during peak demand hours
- Gym: Busiest 5-7 PM (post-work)
3. Astronomy and Earth Science
The hour reflects Earth's rotation:
-
Earth's rotation:
- 360° in ~24 hours = 15° per hour
- Solar noon: Sun crosses local meridian (highest point in sky)
- Local solar time: Based on sun position (varies with longitude)
- Mean solar time: Averaged over year (accounts for orbital eccentricity)
-
Equation of time:
- Sundial time vs. clock time can differ by ±16 minutes
- Due to Earth's elliptical orbit and axial tilt
- Clock time is averaged over the year
-
Hour angle (astronomy):
- Angular distance (in hours) from local meridian
- 1 hour = 15° of celestial sphere rotation
- Used to determine star positions for telescope pointing
-
Sidereal vs. solar day:
- Sidereal day: 23 hours 56 minutes 4 seconds (rotation relative to stars)
- Solar day: 24 hours (rotation relative to sun)
- Difference: Earth moves along orbit, sun appears to shift ~1° per day
4. Energy and Power Consumption
Energy usage measured in watt-hours:
-
Kilowatt-hour (kWh):
- Energy used by 1 kilowatt (1,000 watts) running for 1 hour
- Standard unit for electricity billing
- Average US home: 30 kWh per day (877 kWh per month)
-
Appliance energy use:
- 100W light bulb for 10 hours = 1 kWh
- Electric oven: 2-3 kWh per hour of use
- Central AC: 3-5 kWh per hour
- Laptop: 0.05 kWh per hour (50 watts)
- Refrigerator: 1-2 kWh per day (constant running)
-
Time-of-use pricing:
- On-peak hours: Higher electricity rates (typically 1-9 PM)
- Off-peak hours: Lower rates (typically 9 PM - 9 AM)
- Encourages load shifting to flatten demand curve
-
Battery capacity:
- Milliamp-hour (mAh) or watt-hour (Wh)
- Phone battery: 3,000 mAh (11 Wh) ≈ 2-3 hours screen-on time
- Laptop battery: 50-100 Wh ≈ 5-10 hours use
- Electric car: 60-100 kWh ≈ 250-400 miles range
5. Healthcare and Medicine
Medical dosing and monitoring uses hours:
-
Medication schedules:
- "Every 4 hours" = 6 times per day
- "Every 6 hours" = 4 times per day (QID: quater in die)
- "Every 8 hours" = 3 times per day (TID: ter in die)
- "Every 12 hours" = 2 times per day (BID: bis in die)
- "Every 24 hours" = 1 time per day (QD: quaque die)
-
Drug half-life:
- Time for drug concentration to decrease by half
- Acetaminophen: 2-3 hours
- Caffeine: 5-6 hours
- Alcohol: Eliminated at ~0.015% BAC per hour
-
Fasting requirements:
- Pre-surgery: 8-12 hours fasting (NPO: nil per os)
- Cholesterol test: 9-12 hours fasting
- Glucose tolerance test: 8-hour overnight fast
-
Labor and delivery:
- Labor stages measured in hours
- First stage: 6-12 hours (first baby), 4-8 hours (subsequent)
- Active labor: Cervical dilation ~1 cm per hour
- Pushing stage: 1-3 hours (first baby), 15 min-2 hours (subsequent)
-
Medical shift lengths:
- Resident work-hour restrictions: Max 80 hours per week, max 24-hour shifts
- Nurse shifts: Typically 8 or 12 hours
- Concerns about fatigue and patient safety
6. Computing and Technology
Hours measure uptime and usage:
-
Server uptime:
- "Five nines" (99.999%): 5.26 minutes downtime per year
- "Four nines" (99.99%): 52.6 minutes downtime per year
- "Three nines" (99.9%): 8.77 hours downtime per year
- Measured in hours of continuous operation
-
Data retention:
- Backup schedules: Hourly, daily, weekly
- Log rotation: Every 24 hours (daily logs)
- Cloud storage: Deleted items retained 30 days (720 hours)
-
Usage tracking:
- Screen time: Hours per day on devices
- YouTube Creator Studio: Watch hours (4,000 hours past year for monetization)
- Video games: "Hours played" stat
- Social media: "You've been using this app for 2 hours today"
-
Rendering and processing:
- Video rendering: "2 hours to render 10-minute 4K video"
- 3D modeling: "12-hour render time for scene"
- Machine learning training: "Training took 100 GPU-hours"
7. Legal and Regulatory
Many laws reference hours:
-
Work hour regulations:
- Fair Labor Standards Act (FLSA): 40-hour work week threshold
- Overtime pay: Time-and-a-half for hours beyond 40/week
- Maximum driving hours: Truckers limited to 11 hours driving per 14-hour window
-
Alcohol service hours:
- Many states prohibit alcohol sales certain hours (e.g., 2 AM - 6 AM)
- "Last call": Final hour for ordering drinks
-
Quiet hours:
- Residential noise ordinances: Often 10 PM - 7 AM
- College dorms: 11 PM - 8 AM weeknights
-
Statute of limitations:
- Measured in years, but technically hours
- Parking tickets: Often 72-hour (3-day) payment window
- Right to return/refund: 24-48 hour windows
Additional Unit Information
About Minute (min)
How many seconds are in a minute?
Exactly 60 seconds. This has been standardized since medieval times and is based on the Babylonian base-60 (sexagesimal) number system. Since 1967, when the second was redefined using atomic cesium-133 clocks, one minute equals precisely 60 atomic seconds, or 551,558,906,200 oscillations of caesium-133 radiation.
How many minutes are in an hour?
Exactly 60 minutes. This also comes from Babylonian mathematics. The hour was divided into 60 "first small parts" (Latin: pars minuta prima = minutes), just as each minute is divided into 60 "second small parts" (Latin: pars minuta secunda = seconds).
Why are there 60 minutes in an hour, not 100?
The base-60 system comes from ancient Babylonian mathematics (c. 3000 BCE). The Babylonians chose 60 because it's highly divisible—it has 12 factors (1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60), making fractions much simpler:
- 1/2 hour = 30 min (whole number)
- 1/3 hour = 20 min (whole number)
- 1/4 hour = 15 min (whole number)
- 1/5 hour = 12 min (whole number)
- 1/6 hour = 10 min (whole number)
Contrast with 100 (decimal): 1/3 of 100 = 33.33... (repeating decimal). The Babylonians had sophisticated astronomy requiring complex divisions, so base-60 was superior.
How many minutes are in a day?
1,440 minutes in one 24-hour day.
Calculation: 24 hours × 60 minutes/hour = 1,440 minutes
Breakdown:
- 12 hours (half day) = 720 minutes
- 6 hours (quarter day) = 360 minutes
- 1 hour = 60 minutes
How many minutes are in a year?
525,600 minutes in a standard 365-day year.
Calculation: 365 days × 24 hours × 60 minutes = 525,600 minutes
This number was popularized by the opening song "Seasons of Love" from the 1996 Broadway musical Rent:
"Five hundred twenty-five thousand, six hundred minutes... How do you measure, measure a year?"
For a leap year (366 days): 527,040 minutes (1,440 more minutes).
What's the difference between a minute of time and an arcminute?
Time minute: A unit of duration equal to 60 seconds.
- Symbol: min (or sometimes just listed as "minutes")
- Used for measuring elapsed time, scheduling, etc.
Arcminute (minute of arc): A unit of angular measurement equal to 1/60 of a degree.
- Symbol: ′ (prime symbol)
- Used in astronomy, navigation, and geographic coordinates
- Example: 40°45′30″N = 40 degrees, 45 arcminutes, 30 arcseconds North latitude
Key connection: In navigation, 1 arcminute of latitude = 1 nautical mile (approximately 1,852 meters). This elegant relationship makes nautical charts and navigation calculations simpler.
Same name, different measurements:
- Both descend from the Latin pars minuta prima (first small part) referring to 1/60 divisions
- Context clarifies which is meant
How do I convert minutes to decimal hours?
Formula: Decimal hours = minutes ÷ 60
Examples:
- 30 minutes = 30 ÷ 60 = 0.5 hours
- 15 minutes = 15 ÷ 60 = 0.25 hours
- 45 minutes = 45 ÷ 60 = 0.75 hours
- 90 minutes = 90 ÷ 60 = 1.5 hours
- 20 minutes = 20 ÷ 60 = 0.333... hours (approximately 0.33)
Common conversions:
- 6 minutes = 0.1 hours (used in legal billing: 0.1 hour increments)
- 12 minutes = 0.2 hours
- 18 minutes = 0.3 hours
- 36 minutes = 0.6 hours
Reverse (decimal hours to minutes): Multiply decimal part by 60
- Example: 1.75 hours = 1 hour + (0.75 × 60) = 1 hour 45 minutes
How do I convert hours:minutes format to just minutes?
Formula: Total minutes = (hours × 60) + minutes
Examples:
- 1:30 (1 hour 30 min) = (1 × 60) + 30 = 90 minutes
- 2:15 (2 hours 15 min) = (2 × 60) + 15 = 135 minutes
- 0:45 (45 minutes) = (0 × 60) + 45 = 45 minutes
- 3:20 (3 hours 20 min) = (3 × 60) + 20 = 200 minutes
- 8:00 (8 hours) = (8 × 60) + 0 = 480 minutes (full work day)
This is useful for calculating total duration, comparing times, or doing time arithmetic.
When did clocks start showing minutes?
Early mechanical clocks (1300s-1650s) had only hour hands because they weren't accurate enough to justify showing minutes. Early clocks could lose or gain 15-30 minutes per day.
Minute hands appeared around 1670-1680, shortly after Christiaan Huygens invented the pendulum clock in 1656, which improved accuracy from ~15 minutes/day error to ~15 seconds/day error—a roughly 60× improvement.
Key timeline:
- 1656: Huygens invents pendulum clock
- 1657: First pendulum clocks built (with minute hands)
- 1670s: Minute hands become standard on quality clocks
- 1675: Balance spring invented (Huygens/Hooke), further improving accuracy
- 1680s: Pocket watches begin including minute hands
- 1700s: Minute display becomes universal
Before this, society didn't need minute-level precision—daily life organized around hours, bells, and approximate times. The pendulum clock created both the technical ability and social need for minute-based scheduling.
Do all countries use minutes the same way?
Yes—the 60-minute hour is universal worldwide. Unlike distance (metric vs. imperial) or temperature (Celsius vs. Fahrenheit), time measurement is globally standardized:
- All countries use 60 seconds per minute
- All countries use 60 minutes per hour
- All countries use 24 hours per day
International Standards:
- ISO 8601 (international date/time standard) uses HH:MM:SS format universally
- Coordinated Universal Time (UTC) is the global time standard
- All time zones are defined as offsets from UTC (e.g., EST = UTC-5, JST = UTC+9)
Cultural differences in time display (not measurement):
- 12-hour format (US, Canada, Australia, Philippines): 3:45 PM
- 24-hour format (most of world, military, aviation): 15:45
- Both systems use the same 60-minute hours—just different notation
Historical exception: During the French Revolution (1793-1805), France briefly tried decimal time with 100-minute hours, but it was abandoned as impractical.
How do stopwatches and timers measure fractions of a minute?
Stopwatches display time more precisely than minutes using minutes:seconds.deciseconds format:
Common formats:
- M:SS (minutes:seconds) — e.g., 3:45 = 3 minutes, 45 seconds
- M:SS.SS (minutes:seconds.centiseconds) — e.g., 3:45.23 = 3 min, 45.23 sec
- H:MM:SS (hours:minutes:seconds) — e.g., 1:23:45 = 1 hr, 23 min, 45 sec
Precision levels:
- Sport timing: Typically to 0.01 seconds (centiseconds)
- Olympic 100m: 9.58 seconds (Usain Bolt world record)
- Lab/scientific stopwatches: To 0.001 seconds (milliseconds)
- Atomic clocks: To nanoseconds (0.000000001 seconds) or better
Digital displays:
- Phone stopwatch: Usually shows minutes:seconds.centiseconds (3:45.67)
- Microwave timer: Usually shows minutes:seconds only (3:45)
- Oven timer: Minutes only for long cooking (45), or minutes:seconds for precise tasks
Fractions of minutes in speech:
- "Three and a half minutes" = 3:30
- "Two minutes thirty seconds" = 2:30
- "Five minutes fifteen seconds" = 5:15
Why do clocks go up to 60 minutes, not continue beyond?
At 60 minutes, the minute counter resets to 0 and the hour increments by 1. This is called modular arithmetic or "clock arithmetic":
- 0 minutes → 1 minute → ... → 59 minutes → 0 minutes (next hour)
- Example: 2:59 PM + 1 minute = 3:00 PM (not 2:60 PM)
Why?
- Babylonian base-60 system: We use 60 as the cycle
- Analog clock design: The minute hand makes one complete circle (360°) per hour, returning to 12
- Mathematical consistency: Just as we don't have 60 seconds (it becomes 1 minute), we don't have 60 minutes (it becomes 1 hour)
Modulo 60:
- In mathematics, this is written as minutes mod 60
- Adding times requires carrying: 45 min + 20 min = 65 min = 1 hr 5 min
- Computer timekeeping uses this logic internally
Exception: Elapsed time can exceed 60 minutes:
- "This meeting lasted 90 minutes" (1 hour 30 minutes)
- Marathon time: 2:15:30 (2 hours, 15 minutes, 30 seconds)
About Hour (h)
How many minutes are in an hour?
Exactly 60 minutes. This comes from the ancient Babylonian base-60 (sexagesimal) number system, which the Egyptians and Greeks adopted for dividing hours. The Latin term "pars minuta prima" (first small part) referred to the first 60-part division of an hour, giving us the modern "minute."
How many seconds are in an hour?
Exactly 3,600 seconds (60 minutes × 60 seconds).
Since 1967, when the second was redefined using atomic caesium-133 clocks, one hour equals:
- 3,600 atomic seconds
- 33,074,688,259,200,000 caesium-133 oscillations (33.07 quadrillion)
This makes the hour one of the most precisely defined units of time in existence.
How many hours are in a day?
Exactly 24 hours in one solar day.
Why 24?
- Ancient Egyptians divided day and night into 12 parts each
- 12 + 12 = 24-hour cycle
- Earth rotates 360° in 24 hours = 15° per hour
- This 15° per hour relationship forms the basis for time zones
Note: A sidereal day (rotation relative to stars) is 23 hours, 56 minutes, 4 seconds, but civil timekeeping uses the 24-hour solar day (rotation relative to the sun).
How many hours are in a year?
8,760 hours in a standard 365-day year.
Calculation: 365 days × 24 hours = 8,760 hours
For a leap year (366 days): 8,784 hours (24 more hours).
Work year: Assuming 40-hour weeks and 52 weeks, a full-time work year is 2,080 work hours (not including holidays or vacation).
Why do we use 12-hour AM/PM instead of 24-hour time?
Historical reasons:
- Ancient Egyptians and Romans divided day and night into 12 parts each
- This became culturally entrenched in English-speaking countries
- 12-hour clocks were simpler to manufacture (only need 1-12 markers)
Why 24-hour format exists:
- Eliminates AM/PM confusion (especially 12:00 AM vs. 12:00 PM)
- Preferred in military, aviation, healthcare, computing for clarity
- Standard in most non-English-speaking countries
- ISO 8601 international standard uses 24-hour format
Current usage:
- 12-hour: US, Canada, Australia, Philippines, parts of UK
- 24-hour: Most of Europe, Asia, Africa, South America, military worldwide
What's the difference between a 24-hour day and Earth's rotation?
Solar day (24 hours): Time for sun to return to same position in sky Sidereal day (23h 56m 4s): Time for Earth to rotate 360° relative to distant stars
Why the difference?
- Earth orbits the sun while rotating
- After one 360° rotation, Earth has moved ~1° along its orbit
- Must rotate an additional ~1° (4 minutes) for sun to return to same position
- 365.25 solar days per year, but 366.25 sidereal days per year (one extra rotation)
Practical impact:
- Astronomers use sidereal time for telescope pointing
- Civil timekeeping uses solar time (24-hour day)
- Stars rise ~4 minutes earlier each day (sidereal effect)
How do Daylight Saving Time changes work?
Spring forward (start of DST):
- Clocks advance 1 hour at 2:00 AM → becomes 3:00 AM
- The hour from 2:00-3:00 AM doesn't exist that day
- Day has only 23 hours
- "Lose an hour of sleep"
Fall back (end of DST):
- Clocks retreat 1 hour at 2:00 AM → becomes 1:00 AM again
- The hour from 1:00-2:00 AM occurs twice
- Day has 25 hours
- "Gain an hour of sleep"
Global variation:
- Northern Hemisphere: Starts March/April, ends October/November
- Southern Hemisphere: Starts September/October, ends March/April
- Many countries don't observe DST (China, Japan, India, most of Africa)
- Arizona and Hawaii (US states) don't observe DST
Controversy: Growing movement to abolish DST due to health impacts, minimal energy savings.
Why are time zones roughly 15 degrees wide?
Simple math:
- Earth rotates 360° in 24 hours
- 360° ÷ 24 hours = 15° per hour
- Each time zone theoretically spans 15° longitude
Reality is messier:
- Political boundaries: Zones follow country/state borders
- China uses single time zone (UTC+8) despite spanning 60° longitude (5 theoretical zones)
- India uses UTC+5:30 (half-hour offset from standard)
- Some zones are 30 or 45-minute offsets (Nepal: UTC+5:45)
Practical example:
- Greenwich, England: 0° longitude (Prime Meridian)
- Every 15° east: Add 1 hour (15°E = UTC+1, 30°E = UTC+2, etc.)
- Every 15° west: Subtract 1 hour (15°W = UTC-1, 30°W = UTC-2, etc.)
What is a "billable hour"?
A billable hour is time spent on client work that can be charged to the client, common in legal, consulting, and professional services.
How it works:
- Professionals track time in increments (often 6 minutes = 0.1 hour)
- Multiply hours by hourly rate
- Example: 7.5 billable hours × $300/hour = $2,250
Billing increment examples:
- 6 minutes = 0.1 hour (common in legal)
- 15 minutes = 0.25 hour (quarter-hour)
- Some firms round up to nearest increment
Utilization rate:
- Target: 1,500-2,000 billable hours per year (out of 2,080 work hours)
- Remaining time: Non-billable (admin, business development, training)
- 75-80% utilization considered good in many professions
Ethical concerns:
- Pressure to inflate hours
- Some professions moving to flat-fee or value-based pricing
Can an hour ever be longer or shorter than 60 minutes?
In standard timekeeping: No. An hour is always exactly 60 minutes or 3,600 seconds.
Exceptions and special cases:
-
Leap seconds:
- Very rarely, an extra second added to last minute of day
- Makes that minute 61 seconds, but hour still 3,600 seconds overall
- Last hour of day becomes 3,601 seconds
- 27 leap seconds added 1972-2016
-
Daylight Saving Time transitions:
- "Spring forward": The 2:00 AM hour is skipped (day has 23 hours)
- "Fall back": The 1:00 AM hour occurs twice (day has 25 hours)
- This affects the day length, not individual hour length
-
Historical seasonal hours:
- Ancient/medieval timekeeping used "unequal hours"
- Summer daylight hour ≈ 75 minutes
- Winter daylight hour ≈ 45 minutes
- Obsolete since mechanical clocks standardized equal hours
Future possibility:
- If leap seconds abolished, may use "leap hours" every few centuries instead
Why is rush hour called an "hour" when it lasts 2-3 hours?
Etymology: "Rush hour" originally referred to the peak single hour of commuter traffic, but the term stuck even as traffic congestion expanded.
Modern reality:
- Morning rush: 7:00-9:00 AM (2-3 hours)
- Evening rush: 4:00-7:00 PM (3-4 hours)
- Can extend longer in major cities
Related terms:
- "Peak hours": Broader term for high-traffic periods
- "Congestion pricing": Charging more during rush hours to reduce traffic
- "Off-peak": Outside rush hours, usually smoother travel
Cultural note: The term persists despite inaccuracy, similar to how we still say "dial a phone" or "roll down the window."
Conversion Table: Minute to Hour
| Minute (min) | Hour (h) |
|---|---|
| 0.5 | 0.008 |
| 1 | 0.017 |
| 1.5 | 0.025 |
| 2 | 0.033 |
| 5 | 0.083 |
| 10 | 0.167 |
| 25 | 0.417 |
| 50 | 0.833 |
| 100 | 1.667 |
| 250 | 4.167 |
| 500 | 8.333 |
| 1,000 | 16.667 |
People Also Ask
How do I convert Minute to Hour?
To convert Minute to Hour, enter the value in Minute in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our time converter page to convert between other units in this category.
Learn more →What is the conversion factor from Minute to Hour?
The conversion factor depends on the specific relationship between Minute and Hour. You can find the exact conversion formula and factor on this page. Our calculator handles all calculations automatically. See the conversion table above for common values.
Can I convert Hour back to Minute?
Yes! You can easily convert Hour back to Minute by using the swap button (⇌) in the calculator above, or by visiting our Hour to Minute converter page. You can also explore other time conversions on our category page.
Learn more →What are common uses for Minute and Hour?
Minute and Hour are both standard units used in time measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our time converter for more conversion options.
For more time conversion questions, visit our FAQ page or explore our conversion guides.
Helpful Conversion Guides
Learn more about unit conversion with our comprehensive guides:
All Time Conversions
Other Time Units and Conversions
Explore other time units and their conversion options:
- Second (s) • Minute to Second
- Day (d) • Minute to Day
- Week (wk) • Minute to Week
- Month (mo) • Minute to Month
- Year (yr) • Minute to Year
- Millisecond (ms) • Minute to Millisecond
- Microsecond (μs) • Minute to Microsecond
- Nanosecond (ns) • Minute to Nanosecond
- Decade (dec) • Minute to Decade
- Century (c) • Minute to Century
Verified Against Authority Standards
All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.
National Institute of Standards and Technology — Official time standards and definitions
Bureau International des Poids et Mesures — Definition of the SI base unit for time
Last verified: December 3, 2025