Calculating the area of any shape
Area measures how much flat, two-dimensional space a shape covers, expressed in square units such as square metres or square centimetres. It is one of the most practical calculations in everyday life — you need it to buy the right amount of paint, flooring, turf, fabric, or tiles, and to price jobs that are charged per square metre.
How to use the area calculator
Pick your shape — circle, rectangle, triangle, trapezoid, ellipse, or parallelogram — then enter its dimensions. The calculator applies the correct formula automatically and shows the result. If your measurements are in different units, convert them to the same unit first, or your answer will be wrong.
The formulas behind each shape
A circle is π × r²; a rectangle is length × width; a triangle is ½ × base × height, where the height is measured at a right angle to the base, not along a slanted side. A trapezoid averages its two parallel sides and multiplies by the height: ½(a + b) × h. An ellipse uses π × a × b, and a parallelogram is simply base × height.
A worked example
To turf a circular garden bed with a 3-metre radius, the area is π × 3² ≈ 28.3 square metres. Knowing that, you can order turf with confidence and add a small margin for offcuts. For an irregular room, split it into rectangles and triangles, calculate each piece, and add them together.