180 degrees to radians
3.1416 rad
180° = 3.1416 rad.
radians
3.1416rad
180° = 3.1416 rad
In short
How many radians is 180 degrees?
180° = 3.1416 rad. 1 degree = 0.017453 radians, so the working is 180 × 0.017453 = 3.1416.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 degree = 0.017453 radians 180 × 0.017453 = 3.1416
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (rad) | Off by |
|---|---|---|
| Whole number | 3 | −0.14159 |
| 1 decimal | 3.1 | −0.04159 |
| 2 decimals | 3.14 | −0.00159 |
Round trip: take 3.1416 rad back the other way and you land on 180.0004° — a drift of 0.0004°. That gap is the rounding, not the conversion.
What 180 ° looks like
180 °
A half turn, and exactly π radians. This single equivalence is where the whole 180-over-π conversion factor comes from.
Frequently asked questions
What is 180 degrees in radians?
180 degrees is 3.1416 radians. 1 degree = 0.017453 radians, so the working is 180 × 0.017453 = 3.1416.
How accurate is 3.1416 rad?
Rounding to 3.1416 rad and converting straight back gives 180.0004°, a drift of 0.0004° from the 180 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
Degrees to Radians Converter
Convert degrees to radians — trigonometry, calculus, and anything using π.
Open the degrees to radians converter →