Triangle Calculator

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

Triangle Calculator
A B C c a b a ß ?
Convention:
• Side a = BC, opposite angle a
• Side b = AC, opposite angle ß
• Side c = AB, opposite angle ?
• a + ß + ? = 180°
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Common Triangle Examples

SSS: 3-4-5 Triangle
Right triangle
SAS: a=5, ?=60°, b=6
c ˜ 5.57
ASA: a=45°, c=7, ß=60°
?=75°, a˜5.18, b˜6.29
Right: a=3, b=4
c=5, a=36.87°, ß=53.13°