📐Triangle Calculator

Solve any triangle given sides and angles using the law of sines and cosines.

Enter any combination of sides (a,b,c) and angles (A,B,C) to solve the triangle.

Side a

Side b

Side c

Angle A°

Angle B°

Angle C°

About Triangle Calculator

Solve any triangle given any combination of sides and angles (SSS, SAS, ASA, AAS, SSA). The calculator applies the law of sines and law of cosines to find all missing sides, angles, area, and perimeter. Works for right, acute, and obtuse triangles.

How to Use Triangle Calculator

1
Enter known values
Input the sides and angles you know. Leave the unknowns blank.
2
Solve the triangle
Click Solve to calculate all missing values using the appropriate trigonometric laws.
3
Review full results
See all sides, all angles, perimeter, area, and the type of triangle.

Common Use Cases

Solving trigonometry homework and exam problems
Calculating structural dimensions in engineering and construction
Navigation and surveying calculations
Determining distances and bearings from partial measurements

Frequently Asked Questions

What input combinations are supported?

All standard triangle cases are supported: SSS (three sides), SAS (two sides, included angle), ASA (two angles, included side), AAS (two angles, non-included side), and SSA (two sides, non-included angle — the ambiguous case).

How does it handle the ambiguous SSA case?

When the SSA configuration could produce zero, one, or two valid triangles, the calculator detects this and shows all valid solutions with an explanation.