Convert Arcseconds to Degrees
1 arcsecond is 0.0002778 °. One arcsecond is exactly 0.000277777777778 degrees.
One arcsecond is 2.7778 × 10^-4 degrees. To convert arcseconds to degrees, multiply by 2.7778 × 10^-4; to go the other way, divide by 2.7778 × 10^-4 or multiply by 3600. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Special Publication 811. A 3,600th of a degree.
Factor checked against the defining standard · How we check
- Arcseconds × 2.7778 × 10^-4
1 * 0.00027780 °
1 arcsecond in every angle unit
| Unit | Value | Exact factor |
|---|---|---|
| radians | 0.000004848136811 rad | × 0.0000048481368111 |
| degrees | 0.0002777777778 ° | × 0.000277777777778 |
| gradians | 0.0003086419753 gon | × 0.000308641975309 |
| arcminutes | 0.01666666667 ′ | × 0.0166666666667 |
| arcseconds (as entered) | 1 ″ | — |
| turns | 0.0000007716049383 turn | × 0.000000771604938272 |
| milliradians | 0.004848136811 mrad | × 0.0048481368111 |
Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert arcseconds to degrees? The converter and the working
- 1.Take the measurement in arcseconds.
- 2.Multiply by 2.7778 × 10^-4 — that is how many degrees fit in one arcsecond.
- 3.To go back the other way, divide by 2.7778 × 10^-4, or multiply by 3600.
Worked example: 25 arcseconds to degrees
- Formula
- ″ × 2.7778 × 10^-4 = °
- Arithmetic
- 25 × 2.7778 × 10^-4 = 0.01 °
- Answer
- 25 ″ = 0.01 °
The factor is rounded for display; the figure above is computed from the full value.
Arcseconds to degrees conversion table
| Arcseconds | Degrees |
|---|---|
| 1 ″ | 0.0002778 ° |
| 2 ″ | 0.0005556 ° |
| 3 ″ | 0.0008333 ° |
| 4 ″ | 0.001111 ° |
| 5 ″ | 0.001389 ° |
| 6 ″ | 0.001667 ° |
| 7 ″ | 0.001944 ° |
| 8 ″ | 0.002222 ° |
| 9 ″ | 0.0025 ° |
| 10 ″ | 0.002778 ° |
| 12 ″ | 0.003333 ° |
| 15 ″ | 0.004167 ° |
| 20 ″ | 0.01 ° |
| 25 ″ | 0.01 ° |
| 50 ″ | 0.01 ° |
| 100 ″ | 0.03 ° |
| 200 ″ | 0.06 ° |
| 300 ″ | 0.08 ° |
| 500 ″ | 0.14 ° |
| 1000 ″ | 0.28 ° |
| 2000 ″ | 0.56 ° |
| 5000 ″ | 1.39 ° |
| 10000 ″ | 2.78 ° |
What is an arcsecond?
A 3,600th of a degree. Stellar parallax is measured in these: a star one arcsecond of parallax away is one parsec from Earth, which is where the name comes from.
What is a degree?
A 360th of a full turn, inherited from Babylonian astronomy and its base-60 arithmetic. 360 survives because it divides evenly by everything from 2 to 12 except 7.
How many degrees are in an arcsecond?
One arcsecond is 2.7778 × 10^-4 degrees. Going the other way, one degree is 3600 arcseconds. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every angle unit here
The whole group — 7 units with their symbols and the size of each one in radians — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to an arcsecond.
Source: NIST Special Publication 811 — the radian, and units accepted for use with the SI
Cite this page
- APA
- Rule Calculator. (2026). Convert Arcseconds to degrees. Rule Calculator. https://rulecalculators.com/convert/arcsecond-to-degree
- MLA
- "Convert Arcseconds to degrees." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/arcsecond-to-degree.
- Chicago
- Rule Calculator. "Convert Arcseconds to degrees." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/arcsecond-to-degree.
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Questions people actually ask
- How many degrees are in an arcsecond?
- 2.7778 × 10^-4. A 360th of a full turn, inherited from Babylonian astronomy and its base-60 arithmetic. 360 survives because it divides evenly by everything from 2 to 12 except 7.
- How do I convert degrees back to arcseconds?
- Divide by 2.7778 × 10^-4, or multiply by 3600 — they are the same operation.
Other angle conversions
Degrees to arcseconds — the same conversion the other way.