Trapezoid Area Calculator

How the calculation works

Area = (first parallel base + second parallel base) × perpendicular height / 2.

Worked example

With first parallel base 4 m, second parallel base 8 m, perpendicular height 3 m, area is 18 m².

Assumptions and limits

A flat quadrilateral with the two entered bases parallel. Height is the perpendicular distance between them, not a sloping side. Bases can be entered in either order; equal bases are accepted as the parallelogram case. Enter each length in meters, from 0.001 to 1,000,000. No area is inferred from four side lengths alone.