Solve Right Triangle Calculator

Work out solve right triangle instantly with clear inputs, formula shown and shareable results.

About Solve Right Triangle Calculator

A right triangle is fully determined by any two independent measurements. Pythagoras handles the sides, and the basic ratios sin A = a/c, cos A = b/c and tan A = a/b supply the angles.

Formulas

Pythagoras

a² + b² = c²

Angle from sides

A = arcsin(a / c) = arctan(a / b)

Worked example

With the default values below, Solve Right Triangle Calculator returns Hypotenuse c of 5.0000. Change any input above and every figure here is recalculated in your browser.

Inputs used

What you knowone of Two legs, One leg and the hypotenuse, One leg and an acute angle: Two legs
Leg aminimum 0: 3
Second value (leg b, hypotenuse, or angle in °)minimum 0: 4

Results

Hypotenuse c: 5.0000
Leg a: 3.0000
Leg b: 4.0000
Angle opposite leg a: 36.8699 °

Step by step

1Values used
2Pythagoras
3Angle from sides
4Hypotenuse c= 5.0000
5Leg a= 3.0000
6Leg b= 4.0000
7Angle opposite leg a= 36.8699 °

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Legs 3 and 4?

The hypotenuse is 5 and the angle opposite the leg of 3 is arcsin(0.6) ≈ 36.8699°.

Why must the hypotenuse exceed the leg?

The hypotenuse is always the longest side of a right triangle, so any smaller value describes an impossible triangle.