Complete solution
Triangle
Sides
Classification
Area
Perimeter
Semiperimeter
Inradius
Circumradius
Six triangle workflows
Triangle Calculator
Solve SSS, SAS, ASA/AAS, ambiguous SSA, right triangles or a triangle from coordinates. Then inspect the full geometry, not just the missing side.
Derived geometry
Altitudes hₐ, hᵦ, h𝑐
Medians mₐ, mᵦ, m𝑐
Angle bisectors ℓₐ, ℓᵦ, ℓ𝑐
Longest side / angle
Heron radicand
Validation
OneFreePlace · Free, private triangle solving · Tool #483