Triangle Calculator

Area from base and height, or perimeter and area from three sides (Heron's formula).

Mode:

Base:

Height:

How to use

Pick a mode, enter the sides and click Calculate. Everything runs in your browser — nothing is uploaded or stored.

How do I find area with base 10 and height 4?

Pick “Base & height” — area is 20.

Can it check if sides form a triangle?

Yes — invalid triples are rejected with a message.

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