Example 1
- a = 2
1.732051
What is the height at a = 2? 1.732051. That is √3 after six decimal places.
Equilateral triangle height calculator
Type side a. Equilateral height is a×√3/2. a = 2 gives 1.732051, which is √3. a = 1 gives 0.866025. a = 0 gives 0.
One field, side a. A fraction goes through six decimal places. a = 2 shows 1.732051, not a bare √3. a = 0 leaves 0.
Results
Enter data and click Calculate.
How it works
The height of an equilateral triangle drops from a vertex onto the base at a right angle. The formula is a×√3/2. At a = 2 you have √3. The result is 1.732051, six decimal places.
The field is side a. a = 1 gives half of √3, 0.866025. a = 0 gives 0. a = 6 gives 5.196152, three times √3.
A minus in a gives a minus height. The calculator does not stop the drawing, it only multiplies. This is not the triangle area. Area from the same a is on the neighbouring page and computes a²√3/4.
A third angle from 60° and 60° leaves 60° on the sum-of-angles card. Here you always stay with height from one side.
The header units switch does not multiply anything. 2 stays 1.732051 whatever the label says.
a = 2 gives 1.732051. a = 1 gives 0.866025. a = 0 gives 0.
Formula
h = a × √3 / 2
How to use
- Type side a, for example 2.
- Click Calculate. Height comes out 1.732051.
- a = 1 gives 0.866025. a = 0 gives 0.
- A fraction goes through six decimal places. 2 does not show a bare √3.
- Area from the same a lives on the equilateral area card.
a = 2 gives 1.732051
Equilateral height is a×√3/2. a = 2 gives 1.732051. a = 1 gives 0.866025. a = 0 gives 0.
- height
- a×√3/2. At a = 2 you see 1.732051. At a = 1 you see 0.866025.
- equilateral
- Three equal sides. Here from one a. Area from that a is on the neighbouring page.
- side
- One field a. 0 gives 0. 6 gives 5.196152.
Examples
Example 2
- a = 1
0.866025
What is the height at a = 1? 0.866025. Half of √3.
Example 3
- a = 0
0
What is the height at a = 0? 0. Zero side, zero height.
Related calculators
Common questions
What is the height at a = 2?
1.732051. a×√3/2 = √3, then six decimal places.
What does equilateral triangle height mean?
The segment from a vertex straight down to the base. Formula a×√3/2.
What about a = 1?
0.866025. Half of √3.
What about a = 0?
0. Zero side, zero height.
What about a = 6?
5.196152. Three times √3 after six decimal places.
Is this the triangle area?
No. Area is a²√3/4 on the neighbouring card.
Does 2 show a clean √3?
No. Generic six decimal places leaves 1.732051.
Does a minus in a pass?
Yes. The calculator multiplies. On paper a side is not negative.
Do the units have to be centimetres?
No. 2 stays 1.732051 on the same scale.
Does a comma in 2.0 work?
Yes. 2 and 2.0 give 1.732051.
Knowledge sources
The calculator computes the same formula as the definition below.
Page updated in 2026.