Triangle calculator
Enter any three values, including at least one side. The rest of the triangle is worked out and drawn to scale.
Drawing
Questions people ask
Why can two triangles fit the same values?
When you know two sides and an angle that is not between them (SSA), the third side can swing to two positions. The law of sines gives an angle and its supplement, and both can be valid.
Which formulas are used?
The law of cosines (c² = a² + b² − 2ab·cos C) for three sides or two sides and the angle between them, and the law of sines (a ÷ sin A = b ÷ sin B) for the other cases. Area is ½·ab·sin C.