Trapezoid Area Calculator
Trapezoid area calculator: area from the two parallel sides and the height, or any missing value.
A = (a + b) · h2
How to use this calculator
- Choose the quantity you want under “Solve for”.
- Type the known values and pick their units: any combination works.
- The result updates as you type. Open “Show the steps” to see the substitution.
A = (a + b)·h/2: the average of the two parallel bases times the height.
Formula
A = (a + b) · h2
| Symbol | Quantity | Units |
|---|---|---|
| a | Base a | m, km, cm, mm, µm, nm, pm, Å, in, ft, yd, mi, nmi, au, ly |
| b | Base b | m, km, cm, mm, µm, nm, pm, Å, in, ft, yd, mi, nmi, au, ly |
| h | Height | m, km, cm, mm, µm, nm, pm, Å, in, ft, yd, mi, nmi, au, ly |
| A | Area | m², km², cm², mm², ha, ft², in², yd², ac, mi² |
Worked example
Given: a = 10 cm · b = 6 cm · h = 4 cm
A = (a + b) · h2
Result: A = 32 cm²
Frequently asked questions
Area with bases 10 and 6 cm and height 4 cm?
(10 + 6) × 4 ÷ 2 = 32 cm².