Enter the relevant measurements to calculate triangle area in one consistent unit system.
Inputs
This topic also has a deeper guide and a printable reference pack, so you can move from the live answer into the method, assumptions, and worked examples without leaving the topic cluster.
A stronger guide to right-triangle relationships, triangle area methods, and Heron’s formula, with emphasis on choosing the method that matches the information you actually have.
A stronger geometry guide to area and perimeter, focused on choosing the correct measurement, keeping units consistent, and using decomposition when a shape is not already in textbook form.
A richer geometry reference pack covering area, perimeter, circles, and triangle methods with unit reminders and method-selection guidance.
A more useful worked-examples pack for triangle methods, hypotenuse calculations, and degree-radian relationships.
These are the main values the calculator uses. Keep the units consistent and, where relevant, match the assumptions explained in the related guide.
Unit: units
Enter the value using the unit shown on the field.
Unit: units
Enter the value using the unit shown on the field.
Use this page when you need a fast triangle area result from standard geometric measurements.
Enter dimensions in the same unit unless the page says otherwise. The result reflects the stated formula and the measurements you provide.
Use the Rectangle Area Calculator to calculate rectangle area from the measurements you enter, with clear formulas and consistent units.
Use the Rectangle Perimeter Calculator to calculate rectangle perimeter from the measurements you enter, with clear formulas and consistent units.
Use the Heron Triangle Area Calculator to calculate heron triangle area from the measurements you enter, with clear formulas and consistent units.
Use the Trapezoid Area Calculator to calculate trapezoid area from the measurements you enter, with clear formulas and consistent units.