EVERYDAY CLARITY

Trapezoid Calculator

What is the area of a trapezoid from its parallel bases and height? Enter the values below to calculate the result.

Enter your values

01

Use a dot or comma for decimals.

Your result
area
18 length^2
midline
6 length

Result for the values shown.

Calculations run in your browser.

What to enter
InputMeaning and units
Side a (length)Enter side a in length; use the same basis as the other measurements.
Side b (length)Enter side b in length; use the same basis as the other measurements.
Height (length)Enter height in length; use the same basis as the other measurements.

Understanding your result

Read area (length^2), midline (length) in the units and model stated on this page. The formula midline=(a+b)/2 · area=midline*height defines the relationship; measurement accuracy and model applicability are separate from numerical precision.

Common mistakes

  • Mixing input units or changing the physical meaning of a variable without changing the model.

Check your calculation

  • Use the worked example as a known reference case, then change one input at a time and check the direction and units of the response.

Calculation checks, sources and review limits

What is the area of a trapezoid from its parallel bases and height?

What is the area of a trapezoid from its parallel bases and height? Enter the values below to calculate the result.

Common uses

  • What is the area of a trapezoid from its parallel bases and height

How it works

midline=(a+b)/2; area=midline*height

Worked example

Enter Side a: 4 length; Side b: 8 length; Height: 3 length. Results: area: 18 length^2; midline: 6 length.