Convert Seconds Of Arc to Radians

Enter the angle in seconds of arc below to get the value converted to radians.

Results in Radians:
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1 arcsec = 4.8481E-6 rad

How to Convert Seconds Of Arc to Radians

Protractors are often used to measure angle

To convert a second of arc measurement to a radian measurement, multiply the angle by the conversion ratio. One second of arc is equal to 4.8481E-6 radians, so use this simple formula to convert:

radians = seconds of arc × 4.8481E-6

The angle in radians is equal to the seconds of arc multiplied by 4.8481E-6.

For example, here's how to convert 5 seconds of arc to radians using the formula above.
5" = (5 × 4.8481E-6) = 2.4241E-5 rad

Seconds of arc and radians are both units used to measure angle. Keep reading to learn more about each unit of measure.

Seconds Of Arc

The second of arc is a unit of angle equal to 1/60th of one minute of arc or 1/3,600 of one degree.

A second of arc is sometimes also referred to as an arc second or arcsecond. Seconds of arc can be abbreviated as arcsec, and are also sometimes abbreviated as asec. For example, 1 second of arc can be written as 1 arcsec or 1 asec.

The second of arc is most commonly expressed using a double prime (″), though a double quote is often used as well. For example, 1 second of arc is most often written as 1″.


A radian is the measurement of angle equal to the start to the end of an arc divided by the radius of the circle or arc. 1 radian is equal to 180/π, or about 57.29578°. There are about 6.28318 radians in a circle.

The radian is the SI derived unit for angle in the metric system. Radians can be abbreviated as rad, and are also sometimes abbreviated as c, r, or R. For example, 1 radian can be written as 1 rad, 1 c, 1 r, or 1 R.

Radians are often expressed using their definition. The formula to find radians is θ = s/r, where the angle in radians θ is equal to the arc length s divided by the radius r. Thus, radians may also be expressed as the formula of arc length over the radius.

Second Of Arc Measurements and Equivalent Radian Conversions

Common second of arc values converted to the equivalent radian value
Seconds Of Arc Radians
1" 0.0000048481 rad
2" 0.0000096963 rad
3" 0.000014544 rad
4" 0.000019393 rad
5" 0.000024241 rad
6" 0.000029089 rad
7" 0.000033937 rad
8" 0.000038785 rad
9" 0.000043633 rad
10" 0.000048481 rad
11" 0.00005333 rad
12" 0.000058178 rad
13" 0.000063026 rad
14" 0.000067874 rad
15" 0.000072722 rad
16" 0.00007757 rad
17" 0.000082418 rad
18" 0.000087266 rad
19" 0.000092115 rad
20" 0.000096963 rad
21" 0.000102 rad
22" 0.000107 rad
23" 0.000112 rad
24" 0.000116 rad
25" 0.000121 rad
26" 0.000126 rad
27" 0.000131 rad
28" 0.000136 rad
29" 0.000141 rad
30" 0.000145 rad
31" 0.00015 rad
32" 0.000155 rad
33" 0.00016 rad
34" 0.000165 rad
35" 0.00017 rad
36" 0.000175 rad
37" 0.000179 rad
38" 0.000184 rad
39" 0.000189 rad
40" 0.000194 rad

More Second Of Arc Angle Conversions

Convert to Milliradians
1" is equal to 0.004848 milliradians
Convert to Degrees
1" is equal to 0.000278 degrees
Convert to Minutes Of Arc
1" is equal to 0.016667 minutes of arc
Convert to Gradians
1" is equal to 0.000309 gradians
Convert to Revolutions
1" is equal to 7.716E-7 revolutions
Convert to Circles
1" is equal to 7.716E-7 circles
Convert to Mils (NATO)
1" is equal to 0.004938 mils (NATO)