Trapezoid Area Calculator
Enter the two parallel sides and the height to find a trapezoid's area. Add all four side lengths to find the perimeter as well.
How to find the area of a trapezoid
- Enter the lengths of the two parallel sides.
- Enter the perpendicular height between them.
- Read the area, and add the slanted sides for the perimeter.
Examples
Parallel sides 6 and 10, height 4
a = 6, b = 10, height = 4
area = 32
Perimeter from four sides
sides 6, 10, 5 and 7
perimeter = 28
Frequently asked questions
What is the formula for the area of a trapezoid?
Add the two parallel sides, divide by two, then multiply by the height. This is the average of the parallel sides times the distance between them.
Which sides are the parallel ones?
A trapezoid has exactly one pair of parallel sides, often called the bases. Use those two for the area along with the perpendicular height.
Is a trapezoid the same as a trapezium?
In British English a trapezium is the shape with one pair of parallel sides. The formula and this calculator work the same either way.
How do I find the perimeter?
Add all four side lengths together. The two parallel sides plus the two slanted legs give the full distance around the shape.
What units does this use?
It is unit free. Enter the sides and height in the same unit and the area comes out in square units.
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