# Trapezoid Area Calculator

URL: https://speedycalculator.com/calculators/math/trapezoid/
Last updated: 2026-10-25

> The trapezoid calculator finds the area of a trapezoid (trapezium) from its two parallel sides and the height between them, and gives the median length.

## Inputs

- Parallel side a (m, cm, mm, km, in, ft, yd, mi)
- Parallel side b (m, cm, mm, km, in, ft, yd, mi)
- Height (m, cm, mm, km, in, ft, yd, mi)

## Results

- Area
- Median (midsegment)

## Formula

```
Area = (a + b) ÷ 2 × h
```

## Explanation

A trapezoid’s area equals the average of its parallel sides times its height.

### How to use the Trapezoid Area Calculator

- **Parallel side a**
- **Parallel side b**
- **Height**
- Want to work backwards? Type a value into **Area** and **Height** is calculated for you.

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Add the two parallel sides, halve the sum and multiply by the perpendicular height.

### Inputs explained

FieldWhat to enterParallel side aUnits: m, cm, mm, km, in, ft …Parallel side bUnits: m, cm, mm, km, in, ft …HeightUnits: m, cm, mm, km, in, ft …

### What each result means

- **Area** = ([Parallel side a] + [Parallel side b])÷2 × [Height]
- **Median (midsegment)** = ([Parallel side a] + [Parallel side b])÷2

### Example values

How the main result changes when **Height** changes and everything else stays at the example values above:

Height (m)Area (m²)213319.5426532.5639852

## Worked example

Inputs — Parallel side a: 8 m; Parallel side b: 5 m; Height: 4 m.

Results — **Area = 26 m²**; Median (midsegment) = 6.5 m.

## FAQ

**Is a trapezoid the same as a trapezium?**
In the U.S. “trapezoid”; in the UK and elsewhere “trapezium”.

**Do I need the slanted sides?**
Not for area, only for perimeter.

**What formula does the Trapezoid Area Calculator use?**
Area = (a + b) ÷ 2 × h.

**Can I work backwards from the result?**
Yes. Type the result you want into Area and the calculator finds the matching height.