geometry calculator

Area of a Triangle Calculator

Calculate the area of any triangle using base and height. Perfect for land surveying, architecture, art, sewing patterns or school geometry problems.

Important Use Notice

Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.

Estimate

Enter job values, review the estimate, then use the decision hints before ordering or quoting.

Base of the triangle

Perpendicular height

Estimate Results

Enter values to see the result.

Formula

Area = (base × height) / 2

Base — any side, height — perpendicular distance from opposite vertex to that base.

For equilateral: Area = (side² × √3) / 4

Example

Base 10, height 8 → area 40

Check

Using slanted height instead of perpendicular
Forgetting to divide by 2

Next Step