Angle Converter

Convert degrees, radians, gradians, mils and DMS.

180 degrees =

3.141592654 rad

radians

Conversion factor
1 ° ≈ 0.01745329252 rad
Degrees, minutes, seconds
180° 0′ 0″

Fix the highlighted field to update the result.

Show in all common units
180 ° in other units
UnitValue
degree (°)180 °
radian (rad)3.141592654 rad
gradian (gon) (gon)200 gon
arcminute (′)10,800 ′
arcsecond (″)648,000 ″
turn (turn)0.5 turn
mil (NATO) (mil)3,200 mil

How to use

  1. Type an angle in Value.
  2. Pick the From and To units, or tap a popular conversion.
  3. Read the answer. Degrees, minutes and seconds (DMS) are shown under it.

Formula

A full turn is 360°, which is 2π radians, so 180° = π rad:

radians = degrees × π ÷ 180
degrees = radians × 180 ÷ π
Unit Size
1 radian 180/π ≈ 57.2958°
1 gradian (gon) 0.9° (400 per turn)
1 arcminute (′) 1/60°
1 arcsecond (″) 1/3,600°
1 mil (NATO) 0.05625° (6,400 per turn)

Examples

  • 45° to radians: 45 × π ÷ 180 = π/4 ≈ 0.7854 rad
  • 2.5 rad to degrees: 2.5 × 180 ÷ π = 143.24°
  • 40.4461° as DMS: 0.4461 × 60 = 26.766′, then 0.766 × 60 ≈ 45.96″, so 40° 26′ 45.96″

Conversion charts

Degrees Radians Radians (decimal) Gradians
0° 0 0 0
30° π/6 0.5236 33.33
45° π/4 0.7854 50
60° π/3 1.0472 66.67
90° π/2 1.5708 100
120° 2π/3 2.0944 133.33
180° π 3.1416 200
270° 3π/2 4.7124 300
360° 2π 6.2832 400
Mils (NATO) Degrees
1 0.05625°
10 0.5625°
100 5.625°
1,600 90°
3,200 180°
6,400 360°
More detail: DMS, mils and milliradians
  • DMS to decimal: degrees + minutes ÷ 60 + seconds ÷ 3,600. So 40° 26′ 46″ is 40.4461°.
  • Signs: for south latitudes or west longitudes, put the minus sign on the whole value: −0° 30′ is −0.5°, not +0.5°.
  • Mils: this converter uses the NATO mil, 6,400 per turn. Some other armies have used different counts.
  • Milliradians (mrad) are true thousandths of a radian, about 6,283 per turn. Rifle scopes often use them.

Measuring the sides of a shape too? Use the length converter.

Frequently asked questions

How do I convert degrees to radians?

Multiply by π and divide by 180, because 180° equals π radians. So 90° is π/2, about 1.5708 rad.

How many degrees are in one radian?

About 57.2958°. A radian is the angle at which the arc length equals the radius.

What is a gradian?

One hundredth of a right angle. 400 gradians (gons) make a full turn, so 1 gradian is 0.9°.

How do I convert DMS to decimal degrees?

Add degrees + minutes ÷ 60 + seconds ÷ 3,600. So 40° 26′ 46″ is 40.4461°. For south or west, make the whole value negative.

How many mils are in a circle?

6,400 NATO mils, so 1 mil is 0.05625°. A true milliradian is different: there are about 6,283 in a circle.