Area Calculator
Calculate the area of circles, rectangles, triangles, trapezoids, and ellipses. Shows formula and step-by-step working for each shape.
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Area
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Perimeter / Circumference
Formula Used
Frequently Asked Questions
What is the formula for the area of a circle?
Area = π × r², where r is the radius. For example, a circle with radius 5 cm has area = π × 25 ≈ 78.54 cm².
How do you find the area of a triangle?
Area = ½ × base × height. The height must be perpendicular to the base. For a triangle with base 10 cm and height 6 cm: Area = ½ × 10 × 6 = 30 cm².
What is a trapezoid and how is its area calculated?
A trapezoid (trapezium) has one pair of parallel sides. Area = ½ × (a + b) × h, where a and b are the parallel sides and h is the perpendicular height between them.
What is the difference between area and perimeter?
Area measures the space inside a 2D shape (in square units like cm² or m²). Perimeter measures the distance around the boundary of the shape (in linear units like cm or m).
Why do Nigerian students need to know area formulas?
Area calculations appear in WAEC Mathematics, NECO, and JAMB exams. They are also practical in everyday Nigerian life — measuring plot sizes for land, calculating floor space for tiles, or determining farmland areas.