Area of Equilateral Triangle

The Area of a Equilateral Triangle calculator computes the area of a triangle given the length the triangle's three equal sides.

INSTRUCTIONS: Choose units and enter the following:

• (a) Length of Sides

Triangle Area (A): The  calculator returns the area of the equilateral triangle in square meters.  However, this can be automatically converted to compatible units via the pull-down menu.

The Math Science

The formula for the area of an equilateral triangle is:

`A = sqrt(3)/4   * a^2`

where

• A = area of equilateral triangle
• a = equal length of all tree sides

A triangle is a polygon with three sides, three vertices (corners), and three angles. Triangles can be classified based on the lengths of their sides and the measures of their angles as follows:

By Side Lengths:

• Equilateral Triangle: All three sides are equal in length.
• Isosceles Triangle: Two sides are equal in length.
• Scalene Triangle: All three sides have different lengths.

By Angle Measures:

• Acute Triangle: All three angles are less than 90 degrees.
• Right Triangle: One angle is exactly 90 degrees.
• Obtuse Triangle: One angle is greater than 90 degrees.

The sum of the interior angles of any triangle always adds up to 180 degrees. 

Triangle Calculators

• Area of Triangle (base and height)
• Area of Triangle (two sides and interior angle)
• Area of Triangle (two angles and interior side)
• Area of Triangle (three sides)
• Area of Equilateral Triangle
• Area of Triangle (three points)
• Height of Triangle
• Width of Triangle
• Triangle Perimeter
• Interior Angle of a triangle based on the length of three sides
• Semi-perimeter of a triangle
• Area of Circle Within a Triangle
• Area of Circle Around a Triangle
• Area between two vectors
• Triangle Volume