METHOD
How it is calculated
Rectangle ab; circle πr²; triangle by Heron’s formula; trapezoid (a+b)h/2.
∑ Math and geometry
Area and perimeter calculator
Choose a shape and enter every length in the same unit.
01
Your inputs
Starting values are an example. Replace them with your own.
Your inputs stay in your browser.
02
Your result
Enter your details and run the calculation.
TRACEABLE
Sources and validity
Basic arithmetic or geometry using the formula shown. Uses only your inputs.
How we maintain data ↗