Meter per second to Foot per second Converter
Convert meters per second to feet per second with our free online speed converter.
Quick Answer
1 Meter per second = 3.28084 feet per second
Formula: Meter per second × conversion factor = Foot per second
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.
Meter per second to Foot per second Calculator
How to Use the Meter per second to Foot per second Calculator:
- Enter the value you want to convert in the 'From' field (Meter per second).
- The converted value in Foot per second will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Speed category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Meter per second to Foot per second: Step-by-Step Guide
Converting Meter per second to Foot per second involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Meter per second = 3.28084 feet per secondExample Calculation:
Convert 60 meters per second: 60 × 3.28084 = 196.8504 feet per second
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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.
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Need to convert to other speed units?
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and Standards
The meter per second is defined as:
SI Definition
1 m/s = the velocity of a body that travels a distance of one meter in a time interval of one second.
Formula: v (m/s) = distance (m) / time (s)
SI coherence: The meter per second is a coherent derived unit, meaning it's derived directly from SI base units (meter and second) without numerical factors other than 1.
Why m/s is the "Standard"
Coherent unit integration: Physics equations work directly without conversion factors:
- Force: F = ma → 1 Newton = 1 kg × 1 m/s² (acceleration in m/s²)
- Momentum: p = mv → 1 kg·m/s (velocity in m/s)
- Kinetic energy: KE = ½mv² → 1 Joule = 1 kg × (1 m/s)²
- Power: P = Fv → 1 Watt = 1 N × 1 m/s
If you used km/h or mph, every equation would need messy conversion factors. Using m/s keeps mathematics clean and consistent across all branches of physics and engineering.
Standard Conversions
Metric conversions:
- 1 m/s = 3.6 km/h (exactly, since 1 hour = 3,600 seconds)
- 1 m/s = 0.001 km/s (kilometer per second)
- 1 m/s = 100 cm/s (centimeter per second)
- 1 m/s = 1,000 mm/s (millimeter per second)
Imperial/US conversions:
- 1 m/s = 3.28084 ft/s (feet per second)
- 1 m/s = 2.23694 mph (miles per hour)
- 1 m/s = 196.850 ft/min (feet per minute)
Marine/aviation:
- 1 m/s = 1.94384 knots (nautical miles per hour)
- 1 m/s = 0.00291545 Mach (at sea level, 15°C standard atmosphere)
Relationship to Acceleration
Meters per second squared (m/s²) measures acceleration (rate of change of velocity):
- Gravity: g = 9.8 m/s² (velocity increases 9.8 m/s every second when falling)
- Car acceleration: 0-100 km/h in 5 seconds = average 5.6 m/s² acceleration
- Space shuttle launch: ~30 m/s² (3g) maximum acceleration
and Standards
The foot per second is defined as:
US Customary Definition
1 ft/s = the velocity of a body that travels a distance of one foot in a time interval of one second.
Formula: v (ft/s) = distance (feet) / time (seconds)
Exact SI conversion (since 1959 International Yard and Pound Agreement):
- 1 ft/s = 0.3048 m/s (exactly)
- 1 foot = 0.3048 meters (exactly)
Why ft/s Instead of mph?
Time scale appropriateness: Many technical applications involve sub-second events:
- Ballistics: Bullet flight time measured in milliseconds (0.001 seconds)
- Reaction distance: Driver reaction (1-2 seconds) × speed in ft/s = distance in feet
- Hydraulics: Flow velocities through pipes/channels measured continuously, not per hour
Intuitive scale for small objects:
- "Arrow travels 300 ft/s" vs "arrow travels 205 mph"—ft/s gives clearer sense of per-second distance
- Easier mental math: "How far does projectile travel in 0.1 seconds?" → 30 feet (at 300 ft/s)
Engineering calculations: US hydraulic formulas (Manning's, Darcy-Weisbach) use ft/s natively
Standard Conversions
Imperial/US conversions:
- 1 ft/s = 0.681818 mph (or 15/22 mph exactly)
- 1 ft/s = 3,600 feet/hour
- 1 ft/s = 720 feet/minute
Key conversion (memorize):
- 60 mph = 88 ft/s (exactly: 60 × 5,280 ÷ 3,600 = 88)
- 1 mph = 1.46667 ft/s (or 22/15 exactly)
Metric conversions:
- 1 ft/s = 0.3048 m/s (exactly)
- 1 ft/s = 1.09728 km/h
- 1 ft/s = 30.48 cm/s
Marine/aviation:
- 1 ft/s = 0.592484 knots
- 1 ft/s = 0.000888 Mach (at sea level, 68°F)
Relationship to Acceleration
Feet per second squared (ft/s²) measures acceleration:
- Gravity: g = 32.174 ft/s² (standard gravity, often rounded to 32.2 ft/s²)
- Car acceleration: 0-60 mph in 5 seconds = 88 ft/s ÷ 5 = 17.6 ft/s² average
- Comparison: SI gravity = 9.80665 m/s²
Note: The Meter per second is part of the metric (SI) system, primarily used globally in science and trade. The Foot per second belongs to the imperial/US customary system.
History of the Meter per second and Foot per second
and Evolution
The Metric System Birth (1790s)
French Revolution context: Pre-revolutionary France had hundreds of different units varying by region and trade, causing economic chaos and fraud. The revolutionary government sought rational, universal standards.
The meter (1793):
- Defined as one ten-millionth (1/10,000,000) of the distance from the North Pole to the Equator through Paris
- Physical standard: platinum bar stored in Paris
- Intent: Based on Earth itself, accessible to all nations, unchanging
The second:
- Already standardized internationally as 1/86,400 of a mean solar day
- Based on Earth's rotation (later refined with atomic clocks)
Natural combination: Scientists and engineers naturally combined meters and seconds to express velocity, though initially various fractional units appeared (cm/s in CGS system, km/h for transportation).
19th Century: Scientific Standardization
CGS system (1860s-1870s):
- Centimeter-gram-second system popular in physics
- Velocity often expressed in cm/s (centimeters per second)
- Used in electromagnetism, thermodynamics, fluid dynamics
MKS system (late 1800s):
- Meter-kilogram-second system proposed by Giovanni Giorgi (1901)
- m/s became the practical velocity unit for engineering
- Better suited to human-scale measurements than cm/s
Metre Convention (1875):
- Treaty of the Metre established International Bureau of Weights and Measures (BIPM)
- Standardized meter and kilogram across signatory nations
- Enabled consistent velocity measurements internationally—critical for:
- Ballistics and military applications
- Railway engineering (train speeds, braking distances)
- Early aeronautics and automotive engineering
SI System Adoption (1960)
11th General Conference on Weights and Measures (CGPM, 1960):
- Established the International System of Units (SI)
- Formally designated m/s as the coherent derived unit for velocity
- Unified previously fragmented metric systems (CGS, MKS, MTS)
Coherence principle: SI units multiply and divide to form other SI units without numerical factors:
- Velocity (m/s) = distance (m) / time (s)
- Acceleration (m/s²) = velocity (m/s) / time (s)
- Force (N = kg·m/s²) = mass (kg) × acceleration (m/s²)
- Momentum (kg·m/s) = mass (kg) × velocity (m/s)
Global adoption timeline:
- 1960s-1970s: Scientific community worldwide adopts SI
- 1970s-1980s: Most countries transition official measurements to SI
- 1990s-2000s: International standards (ISO, IEC) require SI units
- Current: ~195 countries use metric system officially; US, Liberia, Myanmar hold out for general use but use SI in science
The Speed of Light Definition (1983)
17th CGPM (1983): Redefined the meter based on the speed of light:
- Speed of light in vacuum: c = 299,792,458 m/s (exactly, by definition)
- The meter is now: the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second
- The second is defined by atomic clocks (cesium-133 hyperfine transition)
Implications:
- Fundamental constant traceability: m/s is now based on fundamental physics (speed of light), not human artifacts (meter bar)
- Ultimate precision: Velocity measurements as accurate as atomic time measurements
- Universal standard: Same meter per second measurement anywhere in universe
and Evolution
Ancient Feet to Modern Standardization
The foot through history:
- Ancient civilizations: Egyptian, Greek, Roman feet varied (285-335 mm)
- Roman pes: ~296 mm (11.65 inches)—basis for many European feet
- Medieval England: Multiple feet existed regionally (London foot, York foot)
- 1588: Queen Elizabeth I attempted standardization
- 1824: British Imperial system defined foot as 1/3 yard
- 1959: International Yard and Pound Agreement defined 1 foot = 0.3048 meters exactly
The second:
- Originally: 1/86,400 of mean solar day (Earth's rotation)
- 1967: Redefined using cesium-133 atomic transition (9,192,631,770 cycles = 1 second)
- Modern definition independent of Earth's rotation (which varies slightly)
The Foot-Pound-Second (FPS) System
British engineering standard (1800s-1960s):
- Length: foot (ft)
- Mass: pound (lb)
- Time: second (s)
- Force: poundal (1 lb·ft/s²) or pound-force (lbf)
- Energy: foot-poundal or foot-pound-force (ft·lbf)
- Velocity: feet per second (ft/s)
FPS system applications:
- Railway engineering: Train speeds, braking distances
- Ballistics: Muzzle velocity, projectile range calculations
- Hydraulics: Water flow in pipes, channels, rivers
- Structural engineering: Wind loads, beam deflections
Decline and persistence:
- 1960: SI system established internationally
- 1970s-1980s: Most countries transitioned to metric
- US holdout: American industry, construction, and firearms sectors retained FPS
- Current: US ballistics universally uses ft/s; engineering mixed (metric in automotive/aerospace, imperial in civil/construction)
Ballistics and the ft/s Standard
Why ballistics uses ft/s:
- Historical momentum: 19th-century firearms development used FPS system
- Industry standardization: Millions of existing specifications in ft/s
- Practical scale: 1,000-3,000 ft/s range fits projectile velocities well
- Reloading data: Powder charge tables, pressure curves all in imperial units
Ammunition velocity standards (all in ft/s):
- .22 LR: 1,200-1,700 ft/s
- 9mm Luger: 1,100-1,300 ft/s
- .45 ACP: 800-900 ft/s
- .223 Remington / 5.56 NATO: 3,000-3,300 ft/s
- .308 Winchester / 7.62 NATO: 2,600-2,800 ft/s
- .50 BMG: 2,800-3,000 ft/s
Chronograph measurements: All ballistic chronographs (devices measuring projectile speed) display in ft/s in US market.
US Hydraulic Engineering
Manning's Equation (open channel flow): v = (1.49/n) × R^(2/3) × S^(1/2)
Where:
- v = velocity in ft/s
- n = Manning's roughness coefficient
- R = hydraulic radius in feet
- S = channel slope (dimensionless)
Note: The 1.49 coefficient is specific to ft/s (metric version uses 1.0 with m/s)
US civil engineering applications:
- Storm drainage design
- Sanitary sewer sizing
- Irrigation canal design
- River and stream analysis
- Flood control structures
Persistence reason: US infrastructure built over 150+ years using imperial units—retrofitting millions of engineering drawings impractical.
Driver Education and Safety
The "60 mph = 88 ft/s" Rule:
Used universally in US driver education to teach reaction distance:
Reaction time (typical): 1.5 seconds Distance traveled (at 60 mph): 1.5 × 88 = 132 feet before braking begins
Stopping distance breakdown (60 mph on dry pavement):
- Reaction distance: 132 feet (time to perceive, react, move foot to brake)
- Braking distance: ~180 feet (actual braking to stop)
- Total stopping distance: ~312 feet (longer than a football field!)
Why ft/s is better than mph for this:
- Intuitive: "I travel 88 feet every second at highway speed"
- Easy calculation: seconds × ft/s = feet
- Using mph requires: mph × 1.467 × seconds = feet (harder mental math)
Common Uses and Applications: meters per second vs feet per second
Explore the typical applications for both Meter per second (metric) and Foot per second (imperial/US) to understand their common contexts.
Common Uses for meters per second
Across Industries
Physics and Scientific Research
- Fundamental constant: All velocity measurements in research papers reported in m/s
- Kinematics: Position, velocity, acceleration equations use m/s and m/s²
- Dynamics: Force, momentum, energy calculations require m/s for SI coherence
- Relativity: Velocities expressed as fractions of c (speed of light in m/s)
Engineering
- Mechanical engineering: Shaft speeds, piston velocities, fluid flow rates in m/s
- Civil engineering: Wind loads, water flow in channels, traffic flow modeling
- Aerospace engineering: Aircraft speeds, rocket velocities, orbital mechanics
- Automotive engineering: Crash testing, braking distances, aerodynamic analysis
Meteorology and Climate Science
- Wind speed: Anemometers calibrated in m/s, weather models use m/s internally
- Storm classification: Hurricane/typhoon wind speeds in m/s (Saffir-Simpson scale)
- Atmospheric circulation: Jet stream velocities, air mass movements
- Ocean currents: Surface and deep ocean current speeds in m/s
Sports Science and Biomechanics
- Performance analysis: Sprint speeds, swimming velocities, ball speeds
- Equipment testing: Golf club head speed, tennis racket velocity, baseball pitch speed
- Injury prevention: Impact velocities, deceleration rates during collisions
- Training optimization: Treadmill speeds, cycling power-to-velocity relationships
Robotics and Automation
- Motion control: Robot arm velocities, conveyor belt speeds
- Autonomous vehicles: Speed sensing, collision avoidance calculations
- Drones: Flight speed control, stability algorithms
- Manufacturing: CNC machine tool speeds, assembly line velocities
When to Use feet per second
Across Industries
Ballistics and Firearms
- Ammunition specifications: All US ammo rated in ft/s muzzle velocity
- Chronograph testing: Velocity measurement devices display ft/s
- Ballistic calculators: Trajectory prediction software requires ft/s input
- Reloading data: Powder charge tables show expected ft/s velocities
Archery and Hunting
- Bow performance: IBO (International Bowhunting Organization) speed ratings in ft/s
- Arrow selection: Spine charts factor in bow speed (ft/s)
- Kinetic energy calculations: KE = (arrow weight × velocity²) ÷ 450,240 (weight in grains, velocity in ft/s → energy in foot-pounds)
US Civil Engineering
- Open channel flow: Manning's equation uses ft/s for rivers, canals, drainage
- Storm water management: Inlet design, detention pond sizing
- Sanitary sewer design: Minimum 2 ft/s to prevent settling
- Flood analysis: Peak flow velocities in ft/s
Driver Education and Safety
- Reaction distance teaching: "At 60 mph, you travel 88 feet every second"
- Following distance: "3-second rule" = 3 × 88 = 264 feet at 60 mph
- Crash reconstruction: Skid mark analysis uses ft/s for velocity calculations
Sports Science
- Baseball/softball: Pitch speed tracking (radar guns display ft/s or mph)
- Golf: Launch monitors measure clubhead and ball speed in ft/s
- Track and field: Sprint speeds converted to ft/s for analysis
Aviation (Limited Use)
- Rate of climb/descent: Feet per minute (fpm), but convertible to ft/s
- Ground speed calculations: Sometimes expressed in ft/s for short-field operations
- Note: Aviation primarily uses knots (nautical miles per hour)
Additional Unit Information
About Meter per second (m/s)
Why do we use m/s instead of km/h in physics?
SI coherence: The meter per second is a coherent SI unit, meaning it combines base SI units (meter, second) without numerical conversion factors. This makes physics equations work directly:
- Force: F = ma where m is kg, a is m/s² → F is Newtons (kg·m/s²)
- Energy: KE = ½mv² where m is kg, v is m/s → KE is Joules (kg·m²/s²)
- Momentum: p = mv where m is kg, v is m/s → p is kg·m/s
If you used km/h, you'd need conversion factors in every equation:
- 100 km/h = 27.78 m/s
- KE = ½ × 1000 kg × (100 km/h)² requires converting km/h to m/s first
- Using m/s keeps math simple and consistent across all physics
How fast is 1 m/s in everyday terms?
1 m/s ≈ slow walking pace
Imagine taking one large step (about 1 meter) every second. That's 1 m/s.
Equivalents:
- 1 m/s = 3.6 km/h = 2.2 mph
- Slower than average walking (1.4 m/s = 5 km/h)
- About the pace of a leisurely stroll
Visual: If you're walking naturally and counting "one Mississippi, two Mississippi," you're covering about 1.4 meters per "Mississippi" (1.4 m/s).
What is the speed of light in m/s?
Exactly 299,792,458 m/s in vacuum (by definition)
This number is exact because the meter is actually defined based on the speed of light:
- 1 meter = distance light travels in 1/299,792,458 of a second
- Since 1983, the meter has been defined this way
Rounded for calculations: c ≈ 3 × 10⁸ m/s (300 million m/s)
In different materials:
- Air: ~299,700,000 m/s (99.97% of vacuum speed)
- Water: ~225,000,000 m/s (75% of vacuum speed)
- Glass: ~200,000,000 m/s (67% of vacuum speed)
How do I convert m/s to knots?
Formula: knots = m/s × 1.94384
Step-by-step example (20 m/s to knots):
- 20 m/s × 1.94384 = 38.9 knots
- Or rough estimate: 20 × 2 = 40 knots
Quick approximation: Multiply by ~2 (actual: 1.944)
Common conversions:
- 10 m/s = 19.4 knots
- 15 m/s = 29.2 knots
- 20 m/s = 38.9 knots (strong wind)
- 25 m/s = 48.6 knots (gale force)
- 30 m/s = 58.3 knots (storm force)
Why knots: One knot = one nautical mile per hour, where 1 nautical mile = 1,852 meters (approximately one minute of latitude).
Is m/s the same as "mps"?
Yes, informally, but m/s is the correct SI symbol.
Accepted notations:
- m/s (official SI symbol, most common)
- m·s⁻¹ (alternative SI notation using negative exponents)
- m s⁻¹ (with space, less common)
- mps (informal abbreviation, spoken English, not official)
Never use:
- m/sec (mix of abbreviations)
- mps with periods (m.p.s.)
- MPS (capital letters change meaning)
In scientific writing: Always use m/s or m·s⁻¹
In speech: "meters per second" or informally "m-p-s" (spelling out letters)
What's the difference between speed and velocity?
Speed: Magnitude only (scalar) — how fast you're moving Velocity: Magnitude + direction (vector) — how fast + which way
Example:
- Speed: "The car is traveling at 30 m/s"
- Velocity: "The car is traveling at 30 m/s north" or "30 m/s at 45° from the x-axis"
In physics:
- Both measured in m/s
- Average speed = total distance / time
- Average velocity = displacement / time (can be zero if you return to start!)
Practical:
- Everyday language often uses "speed" for both concepts
- Physics problems require careful distinction
How fast is the speed of sound in m/s?
343 m/s at 20°C (68°F) at sea level
Temperature dependence: Speed of sound increases with temperature
- 0°C (32°F): 331 m/s
- 15°C (59°F): 340 m/s
- 20°C (68°F): 343 m/s
- 25°C (77°F): 346 m/s
- Formula: v ≈ 331 + 0.6T (where T is temperature in °C)
Altitude effects:
- Sea level: ~343 m/s
- 10,000 m altitude (jet cruise): ~299 m/s (colder air)
- Stratosphere: varies widely with temperature inversions
Other materials (much faster in solids/liquids):
- Water (20°C): 1,481 m/s (4.3× faster than air)
- Steel: 5,960 m/s (17× faster than air)
- Diamond: 12,000 m/s (35× faster than air)
Mach number: Mach 1 = speed of sound in that medium at that temperature
How do you calculate average velocity?
Formula: v_avg = Δx / Δt (displacement / time)
Where:
- Δx = change in position (meters)
- Δt = change in time (seconds)
- Result in m/s
Example 1 (straight line):
- Start: 0 m, End: 100 m, Time: 10 s
- v_avg = (100 - 0) / 10 = 10 m/s
Example 2 (round trip):
- Start: 0 m, travel to 100 m and back to 0 m, Time: 20 s
- v_avg = (0 - 0) / 20 = 0 m/s (displacement is zero!)
- Average speed = 200 m / 20 s = 10 m/s (speed uses total distance, not displacement)
What velocity do you need to reach orbit?
Low Earth Orbit (LEO): ~7,660 m/s (27,600 km/h, 17,150 mph)
Why so fast:
- At this speed, centrifugal force balances gravity
- You're constantly falling toward Earth but moving sideways fast enough to keep missing it
- Orbit is continuous free fall
Velocity by altitude:
- ISS altitude (400 km): 7,660 m/s
- Geostationary orbit (35,786 km): 3,070 m/s (slower because higher orbit)
- Moon's orbit: 1,022 m/s (around Earth at 384,400 km distance)
Escape velocity (leave Earth entirely): 11,200 m/s (40,320 km/h)
Challenge: Rockets must accelerate from 0 to 7,660 m/s while fighting gravity and air resistance—requires enormous energy.
How does wind speed in m/s relate to storm categories?
Beaufort Scale (wind force scale):
- Calm: 0-0.5 m/s
- Light air: 0.5-1.5 m/s
- Light breeze: 1.5-3.3 m/s
- Gentle breeze: 3.3-5.5 m/s
- Moderate breeze: 5.5-8.0 m/s
- Fresh breeze: 8.0-10.8 m/s
- Strong breeze: 10.8-13.9 m/s
- Near gale: 13.9-17.2 m/s
- Gale: 17.2-20.8 m/s
- Strong gale: 20.8-24.5 m/s
- Storm: 24.5-28.5 m/s
- Violent storm: 28.5-32.7 m/s
- Hurricane: >32.7 m/s (>118 km/h, >73 mph)
Saffir-Simpson Hurricane Scale:
- Category 1: 33-42 m/s (119-153 km/h, 74-95 mph)
- Category 2: 43-49 m/s (154-177 km/h, 96-110 mph)
- Category 3: 50-58 m/s (178-208 km/h, 111-129 mph)—major hurricane
- Category 4: 58-70 m/s (209-251 km/h, 130-156 mph)
- Category 5: >70 m/s (>252 km/h, >157 mph)—catastrophic
Can anything travel faster than light?
No physical object can reach or exceed the speed of light (c = 299,792,458 m/s) in vacuum.
Why (simplified):
- As velocity approaches c, relativistic mass increases toward infinity
- Would require infinite energy to accelerate to exactly c
- Only massless particles (photons) travel at exactly c
Things that can "appear" to go faster:
- Phase velocity (wave pattern speed): Can exceed c, but carries no information
- Shadow/spot motion: If you sweep a laser across the Moon, the spot can move faster than c (but it's not a physical object moving)
- Expansion of space: Distant galaxies recede faster than c due to space expansion, not their motion through space
Fastest things (relative to us):
- Photons: c (exactly)
- Neutrinos: ~c (very slightly slower, have tiny mass)
- Fastest spacecraft (Parker Solar Probe): 163,000 m/s = 0.05% of c
About Foot per second (ft/s)
Is ft/s faster than mph?
No—ft/s is a smaller unit, so the number is bigger for the same speed.
- 1 mph = 1.467 ft/s
- 100 ft/s = 68 mph (the ft/s number is bigger, but it's actually slower than "100 mph")
Think of it like inches vs feet: 12 inches = 1 foot. "12" is bigger than "1", but they're the same length. Similarly, "100 ft/s" looks bigger than "68 mph", but they're the same speed.
What is the speed of sound in ft/s?
Approximately 1,125 ft/s at sea level, 68°F (767 mph, 343 m/s) = Mach 1
Temperature dependence:
- 32°F (0°C): 1,087 ft/s
- 68°F (20°C): 1,125 ft/s (standard reference)
- 86°F (30°C): 1,145 ft/s
Practical rule: "Sound travels about 1,100 feet per second"
Lightning distance trick:
- See lightning flash
- Count seconds until thunder: "one Mississippi, two Mississippi, three..."
- Multiply seconds by 1,100 feet
- Divide by 5,280 (feet per mile) to get miles
- Example: 5 seconds → 5,500 feet → ~1 mile away
Why bullets are "supersonic" or "subsonic":
- Supersonic (> 1,125 ft/s): Creates sonic boom/crack
- Subsonic (< 1,125 ft/s): No sonic crack (quieter with suppressor)
How do I convert mph to ft/s in my head?
Method 1 (rough): Multiply by 1.5
- 60 mph × 1.5 = 90 ft/s (actual: 88, close!)
- 40 mph × 1.5 = 60 ft/s (actual: 58.7, pretty close)
Method 2 (better): Use the "22/15 rule" or remember key values
- 30 mph = 44 ft/s
- 60 mph = 88 ft/s
- 90 mph = 132 ft/s
- Scale from these: 45 mph = halfway between 30 and 60 → (44+88)/2 = 66 ft/s
Method 3 (precise): Multiply by 1.467 (or 22/15)
- 50 mph × 1.467 = 73.35 ft/s
Why do bullets use ft/s instead of mph?
Four main reasons:
- Historical: US firearms industry developed using FPS system (foot-pound-second)
- Practical scale: Bullet velocities (1,000-3,000 ft/s) fit well, whereas 700-2,000 mph sounds awkward
- Short-duration events: Bullets travel for fractions of a second, so "per second" is more intuitive than "per hour"
- Ballistic calculations: Easier math for drop (inches), time of flight (milliseconds), energy (foot-pounds) when velocity is in ft/s
Example: .223 Rem bullet at 3,200 ft/s
- Distance in 0.1 seconds: 320 feet (easy mental math)
- If stated as 2,182 mph: distance in 0.1 sec requires mph × 1.467 × 0.1 = 320 feet (harder)
What is terminal velocity in ft/s?
Human skydiver:
- Belly-to-earth (stable, arms/legs spread): 176 ft/s (120 mph, 54 m/s)
- Head-down streamline (diving position): 295 ft/s (200 mph, 90 m/s)
- With parachute deployed: 15-25 ft/s (10-17 mph)—safe landing speed
Other objects:
- Raindrop (small, 1mm): 20 ft/s
- Raindrop (large, 5mm): 30 ft/s
- Baseball: 146 ft/s (100 mph)
- Penny (myth-busting): 30-50 ft/s (not lethal!)
- Bowling ball: 335 ft/s (228 mph)—dangerous!
Why terminal velocity varies: Air resistance balances weight. Bigger, heavier, or more streamlined = higher terminal velocity.
How fast is 300 ft/s in mph?
300 ft/s = 204.5 mph
Formula: 300 ft/s × 0.682 = 204.5 mph
Context: This is a common archery speed (compound bow arrow) or paintball velocity limit (280-300 ft/s)
Comparison:
- 300 ft/s = subsonic (below 1,125 ft/s speed of sound)
- 300 ft/s = 91.4 m/s (metric)
- 300 ft/s = 199 knots (marine/aviation)
What does "subsonic ammo" mean?
Subsonic ammunition: Muzzle velocity < 1,125 ft/s (speed of sound)
Why use subsonic:
- No sonic crack: Supersonic bullets create a sonic boom as they break the sound barrier—sounds like a loud "crack"
- Suppressor-friendly: With a suppressor (silencer), subsonic ammo is much quieter—only the muzzle blast is heard, not the sonic crack
- Hearing protection: Even without suppressor, subsonic is less loud
Common subsonic rounds:
- .45 ACP: 850-900 ft/s (naturally subsonic, heavy bullet)
- 9mm subsonic: 950-1,050 ft/s (special loads, lighter powder charge)
- .22 LR subsonic: 1,050-1,100 ft/s
Supersonic ammunition: Velocity > 1,125 ft/s
- Standard .223 Rem: 3,200 ft/s (almost 3× speed of sound!)
- Standard 9mm: 1,200 ft/s (just barely supersonic)
How far does a car travel in 1 second at 60 mph?
88 feet (exactly)
Breakdown:
- 60 mph = 60 miles/hour
- 60 miles/hour × 5,280 feet/mile ÷ 3,600 seconds/hour = 88 feet/second
Why this matters for safety:
- Reaction time: Average driver takes 1.5 seconds to react to hazard
- Distance during reaction: 1.5 seconds × 88 ft/s = 132 feet (before even touching brake!)
- Braking distance: Additional ~180 feet to stop (dry pavement)
- Total stopping distance: 132 + 180 = 312 feet at 60 mph
Following distance "3-second rule":
- At 60 mph, maintain 3 × 88 = 264 feet behind car ahead
- Gives 2× reaction distance (safer margin)
Can I use ft/s in scientific equations?
Yes, but you must use imperial units consistently:
Kinetic energy (imperial): KE (foot-pounds) = ½ × mass (slugs) × velocity² (ft/s)²
- 1 slug = 32.174 pounds-mass
- Or: KE (ft·lbf) = weight (lbf) × velocity² (ft/s)² / (2 × 32.2)
Force (imperial): F (pound-force) = mass (slugs) × acceleration (ft/s²)
- Or: F (lbf) = (weight in lbf / 32.2) × acceleration (ft/s²)
For scientific work, SI units (m/s, kg, Newtons, Joules) are strongly preferred:
- No slugs vs pounds confusion
- International standards require SI
- Easier unit conversions (all decimal)
Bottom line: You can use ft/s in calculations, but it's more complex than metric. For ballistics and US engineering where ft/s is standard, imperial equations exist. For research/publication, convert to m/s.
What's the difference between ft/s and ft/s²?
ft/s (feet per second): Velocity—how fast you're moving ft/s² (feet per second squared): Acceleration—how quickly your velocity changes
Example (free fall):
- Gravity acceleration: g = 32.2 ft/s²
- After 0 seconds: velocity = 0 ft/s
- After 1 second: velocity = 32.2 ft/s (acceleration added 32.2 ft/s)
- After 2 seconds: velocity = 64.4 ft/s (acceleration added another 32.2 ft/s)
- After 3 seconds: velocity = 96.6 ft/s
Car example (0-60 mph in 5 seconds):
- Change in velocity: 60 mph = 88 ft/s
- Time: 5 seconds
- Average acceleration: 88 ft/s ÷ 5 seconds = 17.6 ft/s²
Conversion Table: Meter per second to Foot per second
| Meter per second (m/s) | Foot per second (ft/s) |
|---|---|
| 0.5 | 1.64 |
| 1 | 3.281 |
| 1.5 | 4.921 |
| 2 | 6.562 |
| 5 | 16.404 |
| 10 | 32.808 |
| 25 | 82.021 |
| 50 | 164.042 |
| 100 | 328.084 |
| 250 | 820.21 |
| 500 | 1,640.42 |
| 1,000 | 3,280.84 |
People Also Ask
How do I convert Meter per second to Foot per second?
To convert Meter per second to Foot per second, enter the value in Meter per second in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our speed converter page to convert between other units in this category.
Learn more →What is the conversion factor from Meter per second to Foot per second?
The conversion factor depends on the specific relationship between Meter per second and Foot per second. 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 Foot per second back to Meter per second?
Yes! You can easily convert Foot per second back to Meter per second by using the swap button (⇌) in the calculator above, or by visiting our Foot per second to Meter per second converter page. You can also explore other speed conversions on our category page.
Learn more →What are common uses for Meter per second and Foot per second?
Meter per second and Foot per second are both standard units used in speed measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our speed converter for more conversion options.
For more speed conversion questions, visit our FAQ page or explore our conversion guides.
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⚖️ Metric vs Imperial
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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 — Standards for speed and velocity measurements
Last verified: December 3, 2025