Trapezoid Area Calculator
Calculate the area of a trapezoid from its parallel side lengths and height, free and instant right in your browser.
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Shape
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How to use this calculator
- Enter the two parallel sides and the height between them.
- Press Calculate for the area.
How it works
The area of a trapezoid (trapezium) is the average of the two parallel sides times the height: (a + b) ÷ 2 × height.
Worked example
Sides 4 m and 6 m, height 2 m. Area = (4 + 6) ÷ 2 × 2 = 10 m².
Frequently asked questions
Which two sides are 'a' and 'b'?
The two parallel sides (the ones that never meet). The height is the perpendicular distance between them.
Is a trapezoid the same as a trapezium?
Yes — 'trapezoid' (US) and 'trapezium' (UK/AU) mean the same four-sided shape with one pair of parallel sides here.
Related tools
- Triangle Area Calculator
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Cite this tool
Zerdly. (2026). Trapezoid Area Calculator. Retrieved from https://www.zerdly.com/tools/trapezoid-area-calculator/
Tip: Enter any known values to calculate the remaining results.
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