Area of a Triangle Calculator
Three formulas: base × height ÷ 2, SAS (two sides and angle), and Heron's (three sides).
Result
Area (½ × base × height)
20.0000 units²
- Method½ × base × height
Step-by-step
- Area = ½ × 8 × 5 = 20.0000.
How to use this calculator
- Pick a method.
- Fill in the values for that method (the third field changes meaning per mode).
- Read the area.
About this calculator
Three classic formulas for triangle area, picked by which inputs you have. Base × height when you have a perpendicular height. SAS (½ a b sin C) when you have two sides and the angle between. Heron's formula when you have all three sides — works for any triangle as long as the three sides satisfy the triangle inequality.
Frequently asked
When you know the three side lengths but not any angles. It's the most general formula.
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