construction calculator
Area Calculator (Rectangle, Circle, Triangle, Trapezoid)
Calculate area for a rectangle, circle, triangle, or trapezoid — fill in only the dimensions your shape needs.
How it works
rectangle = length x width. circle = pi x radius^2. triangle = 0.5 x base x height. trapezoid = 0.5 x (a + b) x height.
Worked example
A 10 ft x 4 ft rectangle = 40 ft2. A 5 ft radius circle = 78.54 ft2.
When to use it
- Pick a shape, then fill only the fields that shape uses; the rest are ignored.
- Universal takeoff input for paint, flooring, and coverage estimates.