Trapezoid Calculator

Find the area, midsegment, and perimeter of a trapezoid. Enter the two parallel sides, the height, and the legs.

Area
— sq units
Average of parallels times height.

Usage Tip

The midsegment of a trapezoid is exactly the average of the two parallel sides — and the area is the midsegment times the height.

THE MATH
area = ((a + b) ÷ 2) × height
midsegment = (a + b) ÷ 2
A trapezoid has one pair of parallel sides (a and b). Its area is the average of those sides times the perpendicular height.
The midsegment connects the midpoints of the legs and equals that average.
The height is the perpendicular distance between the parallel sides, not a leg length.
The legs are used only for the perimeter.
Enter all five lengths in the same units.
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