Unit converter
Angle.
Convert ° to rad, or pick any of the 10 units in the menus. Type in either box and the other follows. Degrees for people, radians for mathematics, and the several different things that have been called a mil.
| ° | rad |
|---|---|
| 1 ° | 0.0174533 rad |
| 2 ° | 0.0349066 rad |
| 3 ° | 0.0523599 rad |
| 4 ° | 0.0698132 rad |
| 5 ° | 0.0872665 rad |
| 10 ° | 0.174533 rad |
| 15 ° | 0.261799 rad |
| 20 ° | 0.349066 rad |
| 25 ° | 0.436332 rad |
| 50 ° | 0.872665 rad |
| 75 ° | 1.309 rad |
| 100 ° | 1.74533 rad |
| 250 ° | 4.36332 rad |
| 500 ° | 8.72665 rad |
| 1000 ° | 17.4533 rad |
- Every unit in the menus is defined against rad, so any pairing converts by the same single route.
Definitions
- The degree divides a full turn into 360, a Babylonian convention that survives because 360 divides so many ways.
- The radian is the SI unit of angle: the angle subtending an arc equal to the radius. A full turn is 2π radians.
- Every unit here is defined against the rad.
- Every unit in the menus is exact by definition, so the only rounding on this page is the one you choose for the display.
How it works
Every value is converted into radians and then back out into the unit you asked for. One route covers every pairing in the menus, so an unusual combination is no less accurate than a common one, and adding a unit affects only that unit.
Both boxes are live. Whichever one you last typed in is the source, changing either menu recalculates straight away, and Swap exchanges the units and the values so the number you are reading stays where you are looking.
Display precision sets a maximum number of significant figures and trims trailing zeroes, so it changes what you see and never what was calculated. The editable box always holds a plain number at full working precision, so you can carry on from either side.
Common questions this answers: how many radians in a degree (0.0174533), how many degrees in a radian (57.2958), and what 180 ° is in radians (3.14159 rad).
Common conversions
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