Area of a Trapezoid Calculator

A = ½ × (parallel side a + parallel side b) × height.

Inputs

Result

Area
32.0000 units²
Average parallel side × height: 8.0000 × 4.
  • a (top)6
  • b (bottom)10
  • Height4
  • Mean of parallels8.0000

Step-by-step

  1. Area = ½ × (6 + 10) × 4 = ½ × 16.00 × 4 = 32.0000.

How to use this calculator

  • Enter the two parallel sides and the perpendicular height between them.
  • Read the area.

About this calculator

A trapezoid (US) or trapezium (UK) has exactly one pair of parallel sides. Its area is the average of the parallel sides times the perpendicular distance between them. Equivalent to a rectangle whose width equals the average of the two parallels.

Frequently asked

Cut the trapezoid horizontally at the midpoint and rotate the top piece — you get a rectangle whose width is the average. Same area.

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