Triangle area (Heron’s formula)
Calculate the area and semi-perimeter of any valid triangle from the lengths of its three sides.
Open calculatorArea (πr²)
28.2743
Circumference (2πr)
18.8496
Diameter (2r)
6
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If you are starting from the diameter, divide it by 2 before entering it as the radius.
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Educational estimate only. Not medical, tax, legal or financial advice.