Advanced Triangle Calculator

Calculate triangle area using Heron's formula from three side lengths. Also computes perimeter and inradius.

Area (Heron's)

14.6969

Perimeter18.0000
Inradius1.6330

Triangle Area via Heron's Formula

Formula

s = (a + b + c) / 2 (semi-perimeter)

Area = sqrt(s × (s-a) × (s-b) × (s-c))

Heron's formula computes the area of any triangle when you know all three side lengths, without needing height or angles.

Inradius

The inradius (radius of the inscribed circle) is: r = Area / s

Example Calculation

Triangle with sides 5, 6, 7.

  1. 01s = (5+6+7)/2 = 9
  2. 02Area = √(9 × 4 × 3 × 2) = √216 ≈ 14.6969
  3. 03Inradius = 14.6969 / 9 ≈ 1.6330

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