Geometry Tool

Solve almost any triangle from three known values.

Enter any three known values with at least one side. This solver handles SSS, SAS, ASA, AAS, and the tricky SSA case where two valid triangles may exist.

Accepted input sets Three values total. At least one side is required. Angles must sum to less than 180° before solving.
What you get back All side lengths, all angles, perimeter, area, height to side c, and a live triangle sketch.

Known Values

Leave unknown fields blank. Side lengths can use any unit as long as all sides use the same one.

Quick Examples

Results

Ready. Enter exactly three known values, with at least one side, then click Solve Triangle.
A B C c b a

Triangle notation uses standard convention: side a is opposite angle A, side b is opposite B, and side c is opposite C.