Calculadora de Área do Trapézio
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
A = (B + b) × h / 2
About this calculator
This calculator determines the area of a trapezoid from the lengths of the longer base, shorter base, and height. A trapezoid is a quadrilateral with two parallel sides, called bases. The height is the perpendicular distance between these bases. The formula used is A = (B + b) × h / 2, where B is the longer base, b is the shorter base, and h is the height.
To use the tool, enter the required values in any unit of length (meters, centimeters, etc.) and click calculate. The result will be displayed in the same unit squared (m², cm²). The calculator is useful for geometry students, engineers, architects, and construction professionals who need to compute areas of trapezoidal land, parts, or projects.
Examples of application include calculating the area of a trapezoidal plot for planting or construction planning, the area of a metal part for material estimation, or the area of a geometric figure in math problems. Remember that the bases and height must be in the same unit for a coherent result.
Important precautions: ensure the height is truly perpendicular to the bases, not the length of a slanted side. In isosceles or right trapezoids, the height can be obtained using the Pythagorean theorem if needed. Also, correctly identify the longer and shorter bases.
Frequently asked questions
What is the formula for the area of a trapezoid?
The formula is A = (longer base + shorter base) × height / 2.
Can I use any unit of measurement?
Yes, as long as all measurements are in the same unit. The result will be in that unit squared.
How do I find the height if it is not given?
If the trapezoid is isosceles or right, the height can be calculated using the Pythagorean theorem from the slanted sides and the difference of the bases.
What if I don't know which base is longer?
The longer base is the longer parallel side. If they are equal, the trapezoid is a parallelogram and the formula still works.
Does the calculator work for trapezoids with slanted non-parallel sides?
Yes, as long as you input the perpendicular height between the bases, not the length of the slanted side.