Triangle Area Calculator
Calculate triangle area using base and height or three sides (Heron's formula). Fast, accurate, and easy to use.
Calculate from Base and Height
Calculate from Three Sides (Heron's Formula)
Triangle Area Formulas
Base & Height
Example: b = 10, h = 6, A = ½ × 10 × 6 = 30 square units
Heron's Formula
where s = (a+b+c)/2 is the semi-perimeter
How to Use This Calculator
Choose Method
Select "Base & Height" if you know these measurements, or "Three Sides" if you know all three side lengths.
Enter Values
Input the measurements. For base & height, enter both values. For three sides, enter all three side lengths.
Calculate
Click Calculate to get the triangle area instantly. The calculator will validate that the sides can form a valid triangle.
Example Calculations
Garden Plot
A triangular garden has a base of 12 meters and height of 8 meters. What is its area?
Triangle with Three Sides
A triangle has sides of 5, 6, and 7 units. What is its area?
Where Triangle Area Calculations Are Used
Architecture & Construction
Calculate roof areas, triangular windows, gable ends, and structural supports. Essential for material estimation and cost planning.
Land Surveying
Measure irregular land plots by dividing them into triangles. Used in property boundaries, topographic mapping, and land valuation.
Education & Geometry
Fundamental concept in school mathematics, geometry courses, and standardized tests. Builds foundation for advanced math topics.
Art & Design
Calculate areas for triangular design elements, fabric patterns, and artistic compositions. Used in graphic design and textile work.
Engineering
Design triangular structures, trusses, and support systems. Calculate stress distribution and load-bearing capacities in mechanical systems.
3D Modeling & Graphics
Triangles are the building blocks of 3D models. Calculate surface areas for texturing, rendering, and mesh optimization in computer graphics.
Frequently Asked Questions
What is the formula for triangle area?
The basic formula is A = ½ × base × height. If you only know the three sides, use Heron's formula: A = √(s(s-a)(s-b)(s-c)), where s is the semi-perimeter.
What is Heron's formula?
Heron's formula calculates triangle area from three side lengths: A = √(s(s-a)(s-b)(s-c)), where s = (a+b+c)/2 is the semi-perimeter. It works for any triangle.