Evaluate the six trig functions, their inverses, and the hyperbolic family for any angle — with a live unit-circle visualization. Switch between degrees and radians at any time. The atan2(y, x) helper handles the two-argument arctangent that JavaScript, Python, and C all expose for vector angles.
Pick a value in [−1, 1] for asin/acos, or any real for atan. Output unit matches the toggle above.
Returns the angle of the vector (x, y) measured counter-clockwise from +x. Handles all four quadrants correctly (unlike atan(y/x)).
| angle | sin | cos | tan |
|---|
sin²θ + cos²θ = 1
1 + tan²θ = sec²θ 1 + cot²θ = csc²θ
sin(a ± b) = sin a cos b ± cos a sin b
cos(a ± b) = cos a cos b ∓ sin a sin b
tan(a ± b) = (tan a ± tan b) / (1 ∓ tan a tan b)
sin 2θ = 2 sin θ cos θ
cos 2θ = cos²θ − sin²θ = 1 − 2 sin²θ = 2 cos²θ − 1
tan 2θ = 2 tan θ / (1 − tan²θ)
Hyperbolic:
sinh x = (eˣ − e⁻ˣ)/2 cosh x = (eˣ + e⁻ˣ)/2
cosh²x − sinh²x = 1