Solve any triangle: find the missing sides and angles, the area (Heron’s formula) and the perimeter, and whether it is acute, right-angled or obtuse.
loading toolHow to use the triangle calculator
- Type your numbers in the boxes (pick your currency or units if asked).
- The answer updates as you type: no button to press.
- Copy the result, or share it on WhatsApp with one tap.
Questions
What is Heron’s formula?
Area = √(s(s−a)(s−b)(s−c)), where s is half the perimeter.
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Is it free?
Completely free, with no sign-up, no watermark and no limit on how many times you use it. Light ads keep the site running.
