Find sine, cosine, tangent and their reciprocals for any angle.
Calculated instantly in your browser.
How do you calculate the trigonometric functions of an angle?
Sine, cosine and tangent are the primary functions; cosecant = 1 ÷ sin, secant = 1 ÷ cos and cotangent = 1 ÷ tan. A function is undefined where its denominator is zero, so tangent and secant are undefined at 90°. For example, at 30°, sin = 0.5, cos ≈ 0.866 and tan ≈ 0.577. Enter the angle in degrees or radians.
Understanding your result
The trigonometric functions relate an angle to ratios of sides in a right triangle, and extend to all angles via the unit circle. Tangent and secant are undefined at 90° because the cosine is zero there.
Formula and method
sin, cos and tan are the primary functions; cosecant = 1 ⁄ sin, secant = 1 ⁄ cos and cotangent = 1 ⁄ tan. A function is undefined where its denominator is zero.
Worked example
At 30°, sin = 0.5, cos ≈ 0.866 and tan ≈ 0.577.
How to use this tool
- Enter the angle.
- Choose degrees or radians.
- Read the six function values.
Common mistakes to avoid
- Entering radians while the unit is set to degrees, or vice versa.
- Expecting a value for tan(90°), which is undefined.
About the Trigonometry Calculator
The Trigonometry Calculator evaluates all six trigonometric functions — sine, cosine, tangent, cosecant, secant and cotangent — for an angle you enter in degrees or radians.
Who should use this tool
Students, engineers and anyone working with angles and triangles.
Benefits
- All six trig functions at once.
- Degrees or radians input.
- Marks undefined values clearly.
- Shows the angle in radians.
Practical use cases
- Looking up a trig value quickly.
- Checking homework answers.
- Working through a physics or engineering problem.
Frequently asked questions
Degrees or radians — which should I use?
Use whichever your problem is stated in. Set the unit accordingly; the tool also shows the angle converted to radians.
Why is tan undefined sometimes?
Tangent equals sin ÷ cos, so it is undefined wherever cosine is zero — at 90°, 270° and so on.