How to use the equilateral triangle calculator
Find the area, height and perimeter of an equilateral triangle from its side. Enter side length in the field above; the area, height, perimeter are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “equilateral triangle area”, “equilateral height”, “triangle with equal sides”, “calculate equilateral triangle”, “find area”.
Formula
Variables
- a — Side length (cm)
Worked example
With side length = 6 cm, the calculator gives area ≈ 15.58846 cm²; height ≈ 5.196152 cm; perimeter ≈ 18 cm.
Frequently asked questions
What is the equilateral triangle calculator used for?
Find the area, height and perimeter of an equilateral triangle from its side. It helps with questions such as “equilateral triangle area”, “equilateral height”, “triangle with equal sides”.
What is the formula for the equilateral triangle calculation?
Area (cm²) = √(3) / 4 × a × a. Height (cm) = √(3) / 2 × a. Perimeter (cm) = 3 × a. Here a is side length (cm).
What inputs do I need for the equilateral triangle calculator?
You need side length in cm. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the equilateral triangle calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the equilateral triangle result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.