ASA Triangle Solver Calculator

About this calculator

ASA (Angle-Side-Angle) is one of the classic triangle congruence cases: knowing two angles and the side between them is enough to fully determine a triangle. The solver first finds the third angle (angles sum to 180°), then applies the law of sines — a/sin(A) = b/sin(B) = c/sin(C) — to find the two unknown sides, and finally computes the area.

Solving triangles this way is a routine calculation in surveying, navigation, and engineering — for instance, triangulating a distant point's position from two known angles measured at either end of a known baseline, a technique that predates GPS and is still taught as the geometric foundation behind it.