Cosine Calculator

Calculate the cosine of an angle, in degrees or radians.

  • Free to use
  • Accurate results
  • No registration required
  • Works on all devices
Enter an angle (in degrees or radians) to calculate its cosine.
Angle unit

Your result

0.5

Cosine

AI explanation

Formula

cos(angle), converted to radians first if entered in degrees

Worked example

cos(60°)

Worked example: cos(60°)
FieldValue
Angle60
Angle unitdegrees
Cosine0.5

Assumptions

  • Cosine is defined for every real angle and always returns a value between -1 and 1.

Frequently asked questions

What is cosine?

In a right triangle, cosine of an angle is the ratio of the length of the adjacent side to the hypotenuse. More generally, it's defined for any angle using the unit circle.

What is cos(0°)?

Cosine reaches its maximum value of 1 at 0°, since the adjacent side equals the hypotenuse when the angle is zero.

How do I find the angle from a cosine value instead?

Use the Inverse Trigonometry Calculator, which computes arccos (the inverse of cosine).

Related calculators

Report a calculation issue