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Math · Calculator

Triangle Area Calculator

Calculate triangle area from base and height, or from three side lengths using Heron's formula.

Base-height area

30

Heron's formula area

6

Results are deterministic client-side calculations. Review assumptions and units before using a result in school, business, construction, or technical work.

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How to use this calculator

Calculate triangle area from base and height, or from three side lengths using Heron's formula.

How the calculation works

  • Choose base-height or side-length mode.
  • Enter the required measurements.
  • The area is calculated after validation.

Formula

Base-height area = base x height / 2. Heron's formula: sqrt(s(s-a)(s-b)(s-c)).

Example

A triangle with base 10 and height 6 has area 30.

Understanding your result

Use the output as a practical starting point, then review it before using it in an important workflow.

Assumptions and limitations

  • Heron's formula requires side lengths that form a valid triangle.
  • Units are generic; area uses squared units.

Frequently asked questions

Does this require an account?

No. The core tool works without creating a Tool2Do account.

Is my input included in share links or analytics?

No. Tool2Do share actions use the tool page URL and safe metadata, not private values or uploaded files.

Triangle Area Calculator | Tool2Do