Right Triangle Calculator
Calculate the hypotenuse, surface area, perimeter boundary, and side lengths of any right-angled triangle. Solve instantly by inputting any two values.
A right triangle is a triangle in which one angle is a right angle (90 degrees). The relation between the sides and other angles of the right triangle is the basis for trigonometry.
The square of the hypotenuse (c) is equal to the sum of the squares of the other two legs (a and b).
Multiply the base and height legs together, then divide by 2. This represents the total flat 2D space inside.
Sum the lengths of the two legs and the hypotenuse. This represents the total outer boundary path.
Drafting Set Square (30-60-90)
Legs: 10.0 cm × 17.32 cm
Hypotenuse ≈ 20.0 cm | Area ≈ 86.6 cm²
US Letter Paper Sheet Diagonal
Legs (Width & Height): 8.5 in × 11.0 in
Hypotenuse (Diagonal) ≈ 13.9 in | Area ≈ 46.75 in²
Diagonal of a Standard Soccer Pitch
Legs: 105 m × 68 m
Hypotenuse (Diagonal) ≈ 125.1 m | Area ≈ 3,570 m²
Large Sailboat Mainsail (Example)
Legs (Foot & Luff): 15.0 ft × 36.0 ft
Hypotenuse (Leech) ≈ 39.0 ft | Area = 270.0 ft²
| Base Leg (cm) | Height Leg (cm) | Hypotenuse (cm) | Area (cm²) | Perimeter (cm) |
|---|---|---|---|---|
| 3 | 4 | 5 | 6 | 12.000 |
| 5 | 12 | 13 | 30 | 30.000 |
| 8 | 15 | 17 | 60 | 40.000 |
| 7 | 24 | 25 | 84 | 56.000 |
| 20 | 21 | 29 | 210 | 70.000 |
| 12 | 35 | 37 | 210 | 84.000 |
| 9 | 40 | 41 | 180 | 90.000 |
| 11 | 60 | 61 | 330 | 132.000 |