Calculate the area of a triangle. The simplest method is (base × height) ÷ 2. For three sides, use Heron's formula.
How it works
- Enter the base and height of the triangle.
- The calculator applies the standard area formula.
- View the area in the same units squared.
Frequently asked questions
What if I only know the three sides?
Use Heron's formula. Many geometry calculators support both methods.
Does the height have to be inside the triangle?
No. For obtuse triangles the height may fall outside, but the formula still works.
Units?
The result is in square units of whatever you entered (cm², in², etc.).