Skip to content
Mathify

Math

Instant, private, and free

Cosine Calculator.

Calculate cosine for an angle entered in degrees.

On-device calculationNo signup
01

Set your values

Results update as you type.

Angle (rad): 1.047198 rad

Angle (rad)

1.047198rad
Cosine: 0.5

Cosine

0.5

Results update automatically as you type.

Use Cases

Trigonometry homework help

Quickly verify cosine values for angles in degrees, making it easier to check answers or understand trigonometric concepts.

Example: Check that cos(60°) = 0.5.

Physics and engineering calculations

Use cosine values to resolve vectors, calculate work done, or analyze wave functions where angles are in degrees.

Example: Find the horizontal component of a force at 45°.

Frequently Asked Questions

How do I use the cosine calculator?
Enter the angle in degrees in the 'Angle' field and click calculate. The calculator will return the cosine value for that angle.
What is the range of cosine values?
The cosine of any angle is always between -1 and 1, inclusive. For example, cos(0°)=1, cos(90°)=0, and cos(180°)=-1.
Can I enter negative angles?
Yes, you can enter negative angles. The cosine function is even, so cos(-θ) = cos(θ). For instance, cos(-30°) equals cos(30°).

Tips & Common Mistakes

Tips

  • Remember that cosine is periodic with a period of 360°, so cos(θ) = cos(θ + 360°).
  • For angles in radians, convert to degrees first by multiplying by 180/π.
  • Use the calculator to explore symmetry: cos(θ) = cos(-θ) and cos(180° - θ) = -cos(θ).
  • When using the result, consider rounding to the appropriate number of decimal places for your application.

Common Mistakes to Avoid

  • Forgetting to switch your calculator to degree mode when using trigonometric functions.
  • Confusing cosine with sine; ensure you are calculating the correct function.
  • Entering the angle in radians instead of degrees, which will give a different result.

Last updated: August 13, 2026