Trapezoid Calculator
Calculate the area and perimeter of a trapezoid from its two parallel sides, height, and legs.
How it works
- 1Enter the two parallel sides a and b and the height between them.
- 2Enter the two legs (the non-parallel sides) for the perimeter.
- 3Read the area ½ × (a + b) × height and the perimeter.
Use cases
- Find the area of a trapezoidal garden, roof, or plot.
- Estimate material for a tapered panel.
- Check geometry homework on trapezoids.
Frequently asked questions
What is the area formula for a trapezoid?
Area = ½ × (a + b) × height, where a and b are the two parallel sides and height is the perpendicular distance between them.
Which sides are a and b?
a and b are the two parallel sides. The legs c and d are the slanted, non-parallel sides used only for the perimeter.
Is a trapezoid the same as a trapezium?
In US English a trapezoid has one pair of parallel sides; this is called a trapezium in British English. This tool uses the US definition.
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Calculate the area and perimeter of a parallelogram from its base, height, and side.