Trigonometry Calculator
Enter an angle, in degrees or radians, to find its sine, cosine, and tangent.
How sine, cosine, and tangent work
For a right triangle, sine is the ratio of the side opposite an angle to the hypotenuse, cosine is the ratio of the adjacent side to the hypotenuse, and tangent is the ratio of the opposite side to the adjacent side (equivalently, sine divided by cosine).
These functions extend naturally to any angle using the unit circle, which is how this calculator computes them for angles beyond 0-90°, including negative angles.
Frequently asked questions
Why does tangent sometimes show infinity?
Tangent is sine divided by cosine, so when cosine is zero (at 90°, 270°, and their equivalents), tangent is undefined — this calculator shows ∞ in that case.
What's the difference between degrees and radians?
Degrees divide a full circle into 360 equal parts; radians measure angles by arc length relative to the radius, with a full circle equal to 2π radians (about 6.2832).
How do I convert between degrees and radians?
Multiply degrees by π/180 to get radians, or multiply radians by 180/π to get degrees.