Arcsecond to Degree Converter

Convert arcseconds to degrees with our free online angle converter.

Quick Answer

1 Arcsecond = 0.000278 degrees

Formula: Arcsecond × conversion factor = Degree

Use the calculator below for instant, accurate conversions.

Our Accuracy Guarantee

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.

Last verified: February 2026Reviewed by: Sam Mathew, Software Engineer

Arcsecond to Degree Calculator

How to Use the Arcsecond to Degree Calculator:

  1. Enter the value you want to convert in the 'From' field (Arcsecond).
  2. The converted value in Degree will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Angle category.
  4. Click the swap button (⇌) to reverse the conversion direction.
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How to Convert Arcsecond to Degree: Step-by-Step Guide

Converting Arcsecond to Degree involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

° = ″ × 0.000277778

Example Calculation:

1 ″ = 0.000278 °

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.

What is a Arcsecond and a Degree?

1 arcsecond = 1/60 arcminute = 1/3600 degree ≈ 0.000278° ≈ 0.00000485 radians

Symbol: ″ (double prime) or arcsec

Key conversions:

  • 60 arcseconds = 1 arcminute
  • 3600 arcseconds = 1 degree
  • 1 arcsecond ≈ 4.848 × 10⁻⁶ radians

A degree (°) divides a full circle into 360 equal parts. 1° = 1/360 of a full rotation = 60 arcminutes = 3600 arcseconds.

The degree is uniquely divisible:

  • 360 = 2³ × 3² × 5
  • Divisible by: 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180
  • This divisibility made the Babylonian base-60 system practical for navigation and astronomy

Note: The Arcsecond is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Degree belongs to the imperial/US customary system.

History of the Arcsecond and Degree

: Why 360?

Ancient Origins (1800 BCE - Babylonia)

The Babylonians, around 1800 BCE, chose 360 degrees for several practical reasons:

  • Sexagesimal System: Base-60 was their mathematical foundation (still seen in 60 seconds/minute, 60 minutes/hour)
  • Solar Year Approximation: The year has roughly 365 days, and 360 was close enough for early calendars
  • High Divisibility: 360 has 24 divisors—more than any smaller number except highly composite numbers
    • This made navigation with compass bearings straightforward
    • Allows easy division into halves (180°), quarters (90°), thirds (120°), sixths (60°), etc.
  • Astronomical Observation: Ancient astronomers could divide the zodiac into 12 houses (each 30°)

Why Not 100?

The metric system later proposed 100 divisions (gradians), but degrees persisted because:

  • Established Tradition: 2,000+ years of navigation, astronomy, and mathematics built on degrees
  • Natural Divisibility: 360 divides more naturally than 100 for common angles
  • Seamless Sub-division: 1° = 60' = 3600" (arcminutes and arcseconds) flow naturally from base-60
  • Inertia in Navigation: Maritime and aviation industries deeply invested in degree-based instruments

Modern Standardization

  • 1665: The degree symbol (°) officially adopted in European mathematics
  • 1960s: Gradians promoted as "metric alternative" but never gained widespread adoption outside Europe
  • Today: Degrees remain globally dominant; gradians used mainly in French/Swiss surveying

Common Uses and Applications: arcseconds vs degrees

Explore the typical applications for both Arcsecond (imperial/US) and Degree (imperial/US) to understand their common contexts.

Common Uses for arcseconds

Astronomy: Measuring star positions, planetary motion, stellar parallax, and telescope resolution. Surveying: High-precision land measurements and geodetic surveys. GPS Systems: Coordinate precision (1 arcsecond ≈ 30 meters at equator). Optics: Telescope and microscope angular resolution specifications.

When to Use degrees

Navigation: Compass bearings

  • North = 0° (or 360°)
  • East = 90°
  • South = 180°
  • West = 270°

Geometry: Measuring angles in triangles, polygons, and circles

  • Acute angle: 0-90°
  • Right angle: 90°
  • Obtuse angle: 90-180°
  • Reflex angle: 180-360°

Geography: Latitude and longitude coordinates

  • Latitude: 0° (Equator) to ±90° (Poles)
  • Longitude: 0° (Prime Meridian) to ±180°

Construction: Slope angles, roof pitch, ramp grades

  • Wheelchair ramp: 4.76° maximum (1:12 slope)
  • Standard roof pitch: 20-30° (steep roofs 45°+)
  • Stairs: 30-35° typical

Additional Unit Information

About Arcsecond ()

How do I convert arcseconds to degrees?

Formula: Degrees = Arcseconds ÷ 3600

Examples:

  • 3600 arcseconds = 1°
  • 1800 arcseconds = 0.5°
  • 60 arcseconds = 1 arcminute = 0.0167°
  • 1 arcsecond ≈ 0.000278°

Arcseconds to Degrees converter →

How do I convert arcseconds to arcminutes?

Formula: Arcminutes = Arcseconds ÷ 60

Examples:

  • 60 arcseconds = 1 arcminute
  • 120 arcseconds = 2 arcminutes
  • 30 arcseconds = 0.5 arcminutes
  • 3600 arcseconds = 60 arcminutes = 1°

Arcseconds to Arcminutes converter →

How big is 1 arcsecond on Earth's surface?

At the equator: 1 arcsecond ≈ 30.9 meters ≈ 101 feet

Latitude (north-south): Always ≈ 30.9 m per arcsecond Longitude (east-west): Varies by latitude:

  • Equator: 30.9 m
  • 45° latitude: 21.9 m
  • 60° latitude: 15.5 m
  • 80° latitude: 5.4 m

This is why GPS coordinates to arcsecond precision give location within ~30 meters.

What is stellar parallax in arcseconds?

Stellar parallax is the apparent shift in a star's position as Earth orbits the Sun, measured in arcseconds.

Formula: Distance (parsecs) = 1 / Parallax (arcseconds)

Examples:

  • Proxima Centauri: 0.768 arcseconds → 1.30 parsecs (4.24 light-years)
  • Sirius: 0.379 arcseconds → 2.64 parsecs (8.6 light-years)
  • Alpha Centauri A: 0.742 arcseconds → 1.35 parsecs (4.37 light-years)
  • Barnard's Star: 0.547 arcseconds → 1.83 parsecs (5.96 light-years)

The parsec (pc) unit was defined as the distance at which 1 AU creates 1 arcsecond parallax.

About Degree (°)

How do I convert degrees to radians?

Formula: radians = degrees × (π/180) = degrees × 0.01745

Examples:

  • 30° = 0.524 rad = π/6
  • 45° = 0.785 rad = π/4
  • 90° = 1.571 rad = π/2
  • 180° = 3.142 rad = π
  • 360° = 6.283 rad = 2π

Degree to Radian converter →

How do I convert degrees to gradians?

Formula: gradians = degrees × (400/360) = degrees × 1.111

Examples:

  • 90° = 100ᵍ
  • 45° = 50ᵍ
  • 180° = 200ᵍ
  • 360° = 400ᵍ

Degree to Gradian converter →

What's the difference between arcminutes and arcseconds?

  • Arcminute ('): 1/60 of a degree (used in surveying, astronomy)
  • Arcsecond ("): 1/60 of an arcminute = 1/3600 of a degree (used in precise astronomy)
  • Example: The Moon appears to be about 0.5° (30 arcminutes) across from Earth

Finer subdivisions exist but are rarely used outside specialized fields.

Why do we use 360 degrees instead of 100?

Historical reasons primarily:

  • Ancient Babylonian sexagesimal system (base-60) was established 4,000+ years ago
  • 360 is highly divisible: Can divide evenly by 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180
  • 100 is less convenient: Divides nicely by 2, 4, 5, 10, 20, 25, 50—fewer options
  • Maritime/Aviation Inertia: Centuries of tradition in navigation instruments
  • Attempted Reform: The metric system proposed gradians (400 per circle) but never gained traction

The degree persists because it's deeply embedded in global infrastructure.

Can I use decimal degrees in navigation?

Yes, but with caveats:

  • GPS Systems: Use decimal degrees by default (e.g., 40.7128°N, 74.0060°W)
  • Maps: Modern digital maps support decimal degrees
  • Precision Issue: Decimal notation can be confusing for precision
    • 0.001° ≈ 111 meters (at equator)
    • 0.00001° ≈ 1.1 meters
  • Traditional Navigation: Mariners still prefer DMS (degrees/minutes/seconds) for clarity

What angle is a compass bearing of "N 30°E"?

It's 30° clockwise from north, or simply 30° on a standard compass.

  • N 0°E = 0° (due North)
  • N 30°E = 30° (northeast-ish)
  • N 90°E = 90° (due East, but written as simply "E")
  • S 30°E = 150° (southeastish)
  • S 30°W = 210° (southwestish)

This notation is common in surveying and maritime contexts.

What is the latitude/longitude coordinate system?

  • Latitude: Angle north (+) or south (-) of the Equator
    • Equator = 0°
    • North Pole = 90°N
    • South Pole = 90°S
    • Lines of latitude run east-west
  • Longitude: Angle east (+) or west (-) of the Prime Meridian (Greenwich)
    • Prime Meridian = 0°
    • International Date Line ≈ 180°
    • Lines of longitude run north-south

Distance Approximations:

  • 1° latitude ≈ 111 km everywhere
  • 1° longitude ≈ 111 km × cos(latitude)
    • At equator: 111 km
    • At 45°: 78.5 km
    • At poles: approaches 0 km

How precise is GPS in degrees?

| Decimal Places | Precision | Application | |---|---|---| | 0 | ±111 km | Continental scale | | 1 | ±11 km | Country scale | | 2 | ±1.1 km | City scale | | 3 | ±111 meters | Building scale | | 4 | ±11 meters | Street address | | 5 | ±1.1 meters | Tree in forest | | 6 | ±0.11 meters | Surveying | | 7 | ±1.1 cm | Precision surveying | | 8 | ±1.1 mm | Scientific research |

Consumer GPS typically achieves 4-6 decimal places (11m - 1.1m accuracy).

What's the relationship between degrees and percentage grades?

  • Grade (%) = tan(angle) × 100
  • Examples:
    • 5° slope ≈ 8.7% grade (rise 100 feet, run ~1,150 feet)
    • 10° slope ≈ 17.6% grade
    • 45° slope ≈ 100% grade (equal rise and run)

This is why wheelchair ramps (≤4.76° or ≤8.3% grade) are so gradual—they spread distance to minimize slope.

  • 180° = 3.142 rad = π

Degrees to Radians converter →

How many degrees in a circle?

360 degrees = 1 full circle

Also:

  • 90° = quarter circle (right angle)
  • 180° = half circle (straight angle)
  • 270° = three-quarters circle

Why 360 degrees in a circle?

Ancient Babylonians used base 60 mathematics. 360 has many divisors (2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 60, 72, 90, 120, 180) making calculations easier. Also approximates 365 days in a year.

Conversion Table: Arcsecond to Degree

Arcsecond ()Degree (°)
0.50
10
1.50
20.001
50.001
100.003
250.007
500.014
1000.028
2500.069
5000.139
1,0000.278

People Also Ask

How do I convert Arcsecond to Degree?

To convert Arcsecond to Degree, enter the value in Arcsecond in the calculator above. The conversion will happen automatically. Use our free online converter for instant and accurate results. You can also visit our angle converter page to convert between other units in this category.

Learn more →

What is the conversion factor from Arcsecond to Degree?

The conversion factor depends on the specific relationship between Arcsecond and Degree. 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 Degree back to Arcsecond?

Yes! You can easily convert Degree back to Arcsecond by using the swap button (⇌) in the calculator above, or by visiting our Degree to Arcsecond converter page. You can also explore other angle conversions on our category page.

Learn more →

What are common uses for Arcsecond and Degree?

Arcsecond and Degree are both standard units used in angle measurements. They are commonly used in various applications including engineering, construction, cooking, and scientific research. Browse our angle converter for more conversion options.

For more angle conversion questions, visit our FAQ page or explore our conversion guides.

All Angle Conversions

Degree to RadianDegree to GradianDegree to ArcminuteDegree to ArcsecondDegree to TurnDegree to RevolutionDegree to QuadrantDegree to GonDegree to MilRadian to DegreeRadian to GradianRadian to ArcminuteRadian to ArcsecondRadian to TurnRadian to RevolutionRadian to QuadrantRadian to GonRadian to MilGradian to DegreeGradian to RadianGradian to ArcminuteGradian to ArcsecondGradian to TurnGradian to RevolutionGradian to QuadrantGradian to GonGradian to MilArcminute to DegreeArcminute to RadianArcminute to GradianArcminute to ArcsecondArcminute to TurnArcminute to RevolutionArcminute to QuadrantArcminute to GonArcminute to MilArcsecond to RadianArcsecond to GradianArcsecond to ArcminuteArcsecond to TurnArcsecond to RevolutionArcsecond to QuadrantArcsecond to GonArcsecond to MilTurn to DegreeTurn to RadianTurn to GradianTurn to ArcminuteTurn to ArcsecondTurn to RevolutionTurn to QuadrantTurn to GonTurn to MilRevolution to DegreeRevolution to RadianRevolution to GradianRevolution to ArcminuteRevolution to ArcsecondRevolution to TurnRevolution to QuadrantRevolution to GonRevolution to MilQuadrant to DegreeQuadrant to RadianQuadrant to GradianQuadrant to ArcminuteQuadrant to ArcsecondQuadrant to TurnQuadrant to RevolutionQuadrant to GonQuadrant to MilGon to DegreeGon to RadianGon to GradianGon to ArcminuteGon to ArcsecondGon to TurnGon to RevolutionGon to QuadrantGon to MilMil to DegreeMil to RadianMil to GradianMil to ArcminuteMil to ArcsecondMil to TurnMil to RevolutionMil to QuadrantMil to Gon

Verified Against Authority Standards

All conversion formulas have been verified against international standards and authoritative sources to ensure maximum accuracy and reliability.

NIST Reference on Constants, Units and Uncertainty

National Institute of Standards and TechnologyFundamental physical constants and unit conversions

BIPM SI Units

Bureau International des Poids et MesuresInternational System of Units (SI) definitions and standards

ISO 80000

International Organization for StandardizationQuantities and units international standards series

Last verified: February 19, 2026