How this degrees to radians calculator works
Enter an angle in degrees. The calculator converts it to radians with Radians = Degrees × π ÷ 180. 180 degrees becomes 3.141593. 90 degrees becomes 1.570796. The result is labelled Radians and shown to six decimal places.
A half turn is 180 degrees and π radians, so the scale factor is π/180. 30 degrees is π/6 ≈ 0.523599. 45 degrees is π/4 ≈ 0.785398. 60 degrees is π/3 ≈ 1.047198. A full turn of 360 degrees is 2π ≈ 6.283185.
Any finite degree value is accepted, including negatives and decimals. −90 degrees is −1.570796. An empty field shows “--.” Despite the page title, this tool does not compute a separate acute reference angle; it only converts the number you type from degrees to radians.
To go back, multiply radians by 180 and divide by π. Many programming and calculus trig functions expect radians, so 90 degrees must be entered as about 1.570796 when the function is in radian mode.