Right Triangle Calculator

Calculate all properties of right triangles from any two known values. Find sides, angles, area, trigonometric ratios, and verify triangle validity with step-by-step solutions.

Right Triangle Calculator

Input Values

Calculate hypotenuse and angles from two perpendicular sides using Pythagorean theorem.
Results

Sides

Side a (opposite to ∠A):3.000 cm
Side b (opposite to ∠B):4.000 cm
Hypotenuse c:5.000 cm

Angles

Angle A:36.870°
Angle B:53.130°
Angle C (right angle):90.000°

Area

6.000 cm²

A = ½ab

Perimeter

12.000 cm

P = a + b + c

Altitude to Hypotenuse

2.400 cm

h = ab/c

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What is Right Triangle Calculator?

A right triangle calculator helps you find all properties of right triangles (triangles with one 90° angle) using various combinations of known values. Right triangles are fundamental in mathematics, physics, engineering, and many practical applications.

Calculation Methods

  • Two Sides:Given two perpendicular sides (a and b), calculate hypotenuse using Pythagorean theorem
  • Hypotenuse & Side:Given hypotenuse and one side, find the other side and all angles
  • Side & Angle:Given one side and one acute angle, calculate all other properties
  • Hypotenuse & Angle:Given hypotenuse and one acute angle, find both sides
  • Verify Triangle:Check if three given sides actually form a right triangle

Right Triangle Properties

  • Sides:Two legs (a and b) and hypotenuse (c, the longest side opposite the right angle)
  • Angles:One right angle (90°) and two complementary acute angles (sum to 90°)
  • Area:½ × base × height = ½ab (using the two legs)
  • Perimeter:Sum of all three sides (a + b + c)
  • Altitude to Hypotenuse:Height from right angle to hypotenuse (h = ab/c)

Special Right Triangles

  • 45-45-90 Triangle:Isosceles right triangle with legs equal, hypotenuse = leg × √2
  • 30-60-90 Triangle:Half of an equilateral triangle with sides in ratio 1 : √3 : 2
  • 3-4-5 Triangle:Classic Pythagorean triple, commonly used in construction
  • 5-12-13 Triangle:Another Pythagorean triple useful for larger measurements

Trigonometric Functions

  • Sine (sin):opposite side ÷ hypotenuse
  • Cosine (cos):adjacent side ÷ hypotenuse
  • Tangent (tan):opposite side ÷ adjacent side
  • Complementary Relationships:sin A = cos B, cos A = sin B (for acute angles A and B)

Key Formulas

  • Pythagorean Theorem:a² + b² = c²
  • Area:A = ½ab (using legs as base and height)
  • Trigonometric Relations:sin² θ + cos² θ = 1
  • Angle Sum:A + B = 90° (for acute angles in right triangle)

Practical Applications

  • Construction:Ensuring square corners, calculating diagonal braces
  • Navigation:Distance and bearing calculations
  • Architecture:Roof pitch, ramp slopes, structural design
  • Surveying:Land measurement and triangulation
  • Physics:Vector components, force analysis



FAQ - Right Triangle Calculator

A right triangle has exactly one angle that measures 90° (a right angle). This creates special relationships between the sides that follow the Pythagorean theorem: the square of the hypotenuse equals the sum of squares of the other two sides (a² + b² = c²).