Trigonometry Calculators
This collection of free trigonometry calculators covers the core operations covered in a standard trig course — from converting between degrees and radians to solving oblique triangles with the law of sines and cosines. Every calculator shows its work step-by-step so you can follow the method, not just get an answer.
What These Calculators Cover
- Degrees & Radians Converter — convert angles in either direction with the formula shown; includes a reference table of common angles
- Sin / Cos / Tan Calculator — compute all six trigonometric functions (sin, cos, tan, csc, sec, cot) for any angle in degrees or radians
- Right Triangle Calculator — solve a right triangle completely from any two known values (two sides, or one side and one angle)
- Law of Sines Calculator — solve oblique triangles given two angles and a side (AAS/ASA) or two sides and a non-included angle (SSA), including the ambiguous case
- Law of Cosines Calculator — solve oblique triangles given two sides and the included angle (SAS) or all three sides (SSS)
- Unit Circle Calculator — look up exact and decimal trig values for any standard angle, with an interactive unit circle diagram
- Inverse Trig Calculator — find the angle (in degrees and radians) from a known sin, cos, or tan value using arcsin, arccos, or arctan
Why Step-by-Step Matters
Trigonometry builds on itself — a wrong sign in the law of cosines or a missed ambiguous case in the law of sines compounds through every subsequent step. These calculators display the complete solution method alongside the answer, so you can check your own work, spot where a mistake occurred, and understand what to do differently next time.
Degrees vs. Radians
All calculators accept input in either degrees or radians. If you are working from a textbook that uses radians, you do not need to convert first — toggle the unit at the top of each calculator. If you need to convert manually, start with the Degrees & Radians Converter.
Solving Triangles: Which Calculator Do You Need?
| Known information | Calculator to use |
|---|---|
| Two sides of a right triangle | Right Triangle Calculator |
| One side + one angle of a right triangle | Right Triangle Calculator |
| Two angles + one side (AAS or ASA) | Law of Sines Calculator |
| Two sides + non-included angle (SSA) | Law of Sines Calculator |
| Two sides + included angle (SAS) | Law of Cosines Calculator |
| Three sides (SSS) | Law of Cosines Calculator |