Triangle Calculator : Solve Area, Perimeter & Angles (Heron & SSS)
The Triangle Calculator solves any valid geometric triangle. Choose between Base & Height mode or 3 Sides (SSS) mode with Heron’s formula to compute area, perimeter, and all three internal angles.
Interactive Calculator
100% Client-Side EngineStep-by-Step Examples
Triangle with Sides 5, 6, 7
Computing area with Heron’s formula.
s = 9. Area = √(9 × 4 × 3 × 2) = √216 ≈ 14.6969.
How to Use This Tool
- Choose your calculation mode: 3 Sides (SSS) or Base & Height.
- Enter the side lengths or base and height.
- Click Calculate to see the area, perimeter, semiperimeter, and internal angles.
Frequently Asked Questions
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