Trigonometry · interactive lab

Degrees, radians & turns

Convert angles in either direction and find the coterminal angle and quadrant.

Degrees, radians & turnsLIVE EXPLORATION
Change a value to see the connection

Your measurements

For π-based input, choose radians and enter a decimal, or use a preset below. Negative angles rotate clockwise.

Why it works

180° = π radians = ½ turn
    A little question. A clearer picture.

    Degrees, radians & turns: common questions

    Wondering about the why? Start here.

    How do I convert degrees to radians?

    Multiply degrees by π/180. For example, 90° = π/2 radians and 360° = 2π radians. To convert back, multiply radians by 180/π. Use a preset or a decimal number for a π-based radian input.

    Understand radians and degrees
    What are coterminal angles?

    Coterminal angles finish in the same direction and differ by whole turns. For example, −90°, 270°, and 630° are coterminal. The converter also shows the equivalent angle from 0° up to, but not including, 360°.

    See angles on the unit circle