Triangle Calculator

Free online triangle calculator to solve any triangle. Calculate sides, angles, area, perimeter, and more with step-by-step solutions.

Triangle Calculator

Calculation Method

Convention:

• Side a = BC, opposite angle α

• Side b = AC, opposite angle β

• Side c = AB, opposite angle γ

• α + β + γ = 180°

Side a units

Side b units

Side c units

SSS: 3-4-5 Triangle

Right triangle

SAS: a=5, γ=60°, b=6

c ≈ 5.57

ASA: α=45°, c=7, β=60°

γ=75°, a≈5.18, b≈6.29

Right: a=3, b=4

c=5, α=36.87°, β=53.13°