Trigonometry calculator (sine, cosine, tangent)

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

Sine (sin)

0.5

Cosine (cos)0.866025

Tangent (tan)0.57735

In radians0.523599

How the calculation works

In a right triangle, sin = opposite/hypotenuse, cos = adjacent/hypotenuse and tan = opposite/adjacent. To compute, degrees are converted to radians (×π/180).

Frequently asked questions

Why is tan 90° undefined?

Because cos 90° is zero, and tangent is sine ÷ cosine (division by zero).

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Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources