Right Triangle Area Calculator
Calculate right triangle area from two legs, leg and hypotenuse, leg and acute angle, hypotenuse and acute angle, or leg and altitude to the hypotenuse.
Right triangle area from legs
The English intent is area-first: the two perpendicular legs are the simplest base and height. Advanced modes recover the missing leg before reporting the same area-focused result set.
A is right triangle area; a and b are the two legs.
c is the hypotenuse.
Supported known values
| Known values | What is calculated |
|---|---|
| Two legs | Area, hypotenuse, perimeter, angles, altitude, and radii. |
| Leg and hypotenuse | Missing leg first, then area. |
| Leg or hypotenuse with an acute angle | Legs by trigonometry, then area. |
| Leg and altitude to hypotenuse | Missing leg by the right-triangle altitude relationship. |
Frequently Asked Questions
Sources and References
- Right Triangle CalculatorCalculator.net
- Right TriangleWolfram MathWorld
- Pythagorean TheoremWolfram MathWorld
Calculations are based on the listed reference sources. Links open in a new tab.
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