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How to use Angle Calculator

Choose the angle type, enter the known angle(s), and the missing or paired angle is calculated instantly.

Frequently asked questions

How do I find a third triangle angle?

The three interior angles of a triangle sum to 180°, so the third angle equals 180° minus the other two.

What are complementary and supplementary angles?

Complementary angles add up to 90°; supplementary angles add up to 180°.

Can it find the complement of any angle?

Yes — enter one angle and it returns both its complement (90° − angle) and supplement (180° − angle).

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