40 degrees to radians
0.6981 rad
40° = 0.6981 rad.
radians
0.6981rad
40° = 0.6981 rad
In short
How many radians is 40 degrees?
40° = 0.6981 rad. 1 degree = 0.017453 radians, so the working is 40 × 0.017453 = 0.6981.
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 40 × 0.017453 = 0.6981
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 | 1 | +0.30187 |
| 1 decimal | 0.7 | +0.00187 |
| 2 decimals | 0.70 | +0.00187 |
Round trip: take 0.6981 rad back the other way and you land on 39.9982° — a drift of 0.0018°. That gap is the rounding, not the conversion.
Frequently asked questions
What is 40 degrees in radians?
40 degrees is 0.6981 radians. 1 degree = 0.017453 radians, so the working is 40 × 0.017453 = 0.6981.
How accurate is 0.6981 rad?
Rounding to 0.6981 rad and converting straight back gives 39.9982°, a drift of 0.0018° from the 40 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
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