About the Law of Sines Calculator
Solve oblique triangles for ASA, AAS, and SSA, with full ambiguous-case handling.
What it is
Not every triangle has a right angle, so not every triangle can be solved with basic trigonometric ratios. The Law of Sines extends trigonometry to any triangle: a/sin A = b/sin B = c/sin C. This tool applies it to ASA, AAS, and SSA problems, including the SSA "ambiguous case" where the height-comparison test (h = bยทsin A) determines whether zero, one, or two triangles satisfy the given measurements.
Features
ASA / AAS / SSA modes
Switch input mode to match the data you have, with only the relevant fields shown.
Ambiguous-case detection
Automatically determines 0, 1, or 2 valid triangles for SSA using the height test.
Step-by-step working
Every unknown is derived from the Law of Sines ratio with your actual numbers shown.
Area, perimeter & diagram
Each valid solution includes its area, perimeter, and a to-scale triangle diagram.