Equilateral Triangle Formulas
2D Shapes
Equilateral Triangle
- Area
- A = (√3 ⁄ 4) a2
- Height
- h = (√3 ⁄ 2) a
- Perimeter
- P = 3a
- a side length
Equilateral Triangle formulas explained
All three sides are equal and every angle is 60°. Area, height and perimeter depend only on the side length. Below are all the equilateral triangle formulas with what each letter means, a worked example and a free calculator.
- Area:
A = (√3 ⁄ 4) a² - Height:
h = (√3 ⁄ 2) a - Perimeter:
P = 3a
Equilateral Triangle calculator
Live calculator
Equilateral Triangle calculator
Worked example: area of a equilateral triangle
Given Side a = 6 cm, substitute the values into each equilateral triangle formula:
- A = (√3 ⁄ 4) × 6² = 15.59 cm²
- h = (√3 ⁄ 2) × 6 = 5.2 cm
- P = 3 × 6 = 18 cm
Equilateral Triangle Formula SheetFormulas, variables, a worked example and practice questions with answers.Download PDFOpen
Equilateral Triangle formulas FAQ
What is the formula for the area of a equilateral triangle?
The area of a equilateral triangle is A = (√3 ⁄ 4) a², where a is the side length.
What is the formula for the height of a equilateral triangle?
The height of a equilateral triangle is h = (√3 ⁄ 2) a, where a is the side length.
What is the formula for the perimeter of a equilateral triangle?
The perimeter of a equilateral triangle is P = 3a, where a is the side length.
Can I download the equilateral triangle formulas as a PDF?
Yes. Use the Download PDF button on this page for a free printable equilateral triangle formula sheet with a worked example and practice questions.
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