Equilateral Triangle Calculator
Calculate the area, height, and perimeter of an equilateral triangle from its side length.
- Height
- 5.1962
- Perimeter
- 18
Formula: A = (√3 / 4) × a²
About Equilateral Triangle Calculator
Equilateral Triangle Calculator is a free online calculator that gives you an instant, accurate result as you type. Calculate the area, height, and perimeter of an equilateral triangle from its side length.
The calculation uses the standard formula A = (√3 / 4) × a² and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
All three angles of an equilateral triangle are exactly 60 degrees, no matter the side length.
Frequently Asked Questions
Is Equilateral Triangle Calculator free to use?
Yes. Equilateral Triangle Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (A = (√3 / 4) × a²) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
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