30-60-90 Triangle Calculator

The 30-60-90 Triangle Calculator solves this specific type of special right triangle with mathematical precision. Essential tool for students, teachers and geometry professionals working with fixed proportions 1:√3:2. Supports input by individual sides, perimeter or area, instantly calculating all values with detailed graphic visualization and explanations of fundamental geometric properties.

Updated at: 06/03/2025

Side opposite to 30° angle (x)

Side opposite to 60° angle (x√3)

Longest side of the triangle (2x)

How the 30-60-90 Triangle Calculator Works

The 30-60-90 triangle calculator is a specialized tool designed to solve right triangles with angles of 30°, 60°, and 90°. By inputting the length of one side—whether it's the short leg, long leg, or hypotenuse—the calculator instantly computes the remaining sides, perimeter, and area. This functionality is particularly beneficial for students, educators, and professionals in fields like geometry, engineering, and architecture.

This calculator leverages the fixed side ratios inherent to 30-60-90 triangles, specifically 1 : √3 : 2. This means that knowing just one side allows for the straightforward determination of the other two, streamlining the problem-solving process.

Understanding the 30-60-90 Triangle

A 30-60-90 triangle is a special type of right triangle characterized by its consistent angle measures of 30°, 60°, and 90°. These triangles are derived by bisecting an equilateral triangle, resulting in two congruent 30-60-90 triangles. The unique properties of these triangles make them a staple in geometric studies and applications.

Fundamental Formulas

The side lengths of a 30-60-90 triangle maintain a consistent ratio, which can be expressed using a variable representing the length of the short leg (opposite the 30° angle):

  • Short Leg (a):

  • Long Leg (b):

  • Hypotenuse (c):

Using these relationships, we can derive formulas for other properties:

  • Area:

  • Perimeter:

These formulas allow for efficient calculations of a triangle's dimensions and properties when one side length is known.

Detailed Examples

Example 1: Given Short Leg

If the short leg :

  • Long Leg

  • Hypotenuse

  • Area

  • Perimeter

Example 2: Given Hypotenuse

If the hypotenuse :

  • Short Leg

  • Long Leg

  • Area

  • Perimeter

Example 3: Given Long Leg

If the long leg :

  • Short Leg

  • Hypotenuse

  • Area

  • Perimeter

These examples illustrate how knowing a single side length enables the determination of all other properties of a 30-60-90 triangle.

What Is the Perimeter of a 30-60-90 Triangle?

The perimeter of a 30-60-90 triangle can be calculated using the formula:

Where is the length of the short leg. This formula simplifies the process of finding the perimeter when the short leg is known.

How to Find the Area of a 30-60-90 Triangle?

To find the area of a 30-60-90 triangle, use the formula:

This formula is derived from the standard area formula for triangles and incorporates the unique side ratios of the 30-60-90 triangle.

Summary Table of Formulas

Known Side Short Leg (a) Long Leg (b) Hypotenuse (c) Area Perimeter
Short Leg (a)          
Long Leg (b)          
Hypotenuse (c)          

This table provides a quick reference for calculating the various properties of a 30-60-90 triangle based on different known side lengths.

Understanding and utilizing these formulas and relationships enable efficient problem-solving involving 30-60-90 triangles in various mathematical and practical contexts.