Trigonometry Calculator
Go from an angle to all six trig functions, from a ratio back to angles, or solve a right triangle. Exact special-angle values and unit-circle context stay beside the decimal answer.
Choose the direction of the problem
Evaluate one angle completely
Radians accept π forms such as pi/6, 3pi/4 and -7π/6.
Find the angle from a ratio
arcsin/arccos require −1 ≤ x ≤ 1. Results show the principal value and all matching angles from 0° to <360°.
π/6 radians
Enter exactly two known values
θ ≈ 36.87° · other angle ≈ 53.13°
Check the core identities at one angle
Decimal and exact forms together
See x = cos θ and y = sin θ
The point on the circle is (cos θ, sin θ). The ray uses the normalized coterminal angle.
Angle steps
- Convert the input angle to radians.
- Read cosine from x and sine from y on the unit circle.
- Build tangent and reciprocal functions from those two values.
Notable unit-circle angles
Tap an angle to load it into the calculator.
| Angle | Radians | sin | cos | tan |
|---|
One exact-value check per UTC day
Same angle for everyone on the date. Choose the correct trig value before opening a calculator.
Use quadrant signs and a reference angle, not memorization alone.
Formulas, conventions & scope
Six functions
On the unit circle, cos θ is x and sin θ is y. tan θ = sin θ / cos θ. The reciprocal functions are sec = 1/cos, csc = 1/sin and cot = cos/sin.
Inverse trig
arcsin, arccos and arctan return principal values, so the calculator also lists every matching angle in one 0°–360° turn. It does not pretend the principal value is the only solution.
Exact values
Exact radicals are shown for the standard 15° family when recognized. For other angles, the calculator reports a decimal value without inventing a symbolic closed form.
Right triangles
SOHCAHTOA mode is deliberately limited to right triangles. For SSS, SAS, ASA/AAS and SSA ambiguous cases, use the separate Triangle Calculator.