Trigonometry · free · no sign-up
Cos calculator
Find the cosine of an angle in degrees or radians.
Cos calculator
Enter your values below and press Calculate to see your result instantly.
cos (
)
Resultant Trigonometric Value
0.5000
ADJACENT-HYPOTENUSE RATIO
1 : 2
SECANT LIMIT (sec)
2.0000
Calculations complete.
About the Cos calculator
Find the cosine of an angle in degrees or radians.
How to use the Cos calculator
- Enter the angle and choose Degrees (°) or Radians (rad).
- Press Calculate.
Formula and method
In a right triangle, cos θ = adjacent ÷ hypotenuse. The value always lies between −1 and 1.
Worked example
cos 60° = 0.5, cos 0° = 1 and cos 90° = 0.
Tips
- Make sure the unit matches your angle.
- cos(−θ) = cos(θ).
Frequently asked questions
What is cos 90°?
Zero.