Estimates for planning and ordering. Every assumption can be changed.
Area calculator
Choose a shape and enter its measurements to see the area in square metres and square feet.
Rates and rules used: 1 foot = 0.3048 metres; 1 square yard = 0.83612736 square metres. Circle area uses π × radius². Sources: Weights and Measures Act 1985 (imperial units). Checked 17th September 2026. Assumptions are typical figures; check your product's own figures.
How area is worked out
A rectangle is length times width. A circle is π (about 3.1416) times the radius squared, where the radius is half the diameter. A triangle is half the base times the height, where the height is measured at right angles to the base.
For an L-shaped room or garden, split it into rectangles, work out each one and add them together. When ordering flooring, turf or paving, allow extra for cutting: 10% is common, more for diagonal layouts.
Common questions
How do I convert square feet to square metres?
Divide by about 10.764. For example, 100 square feet is about 9.29 square metres. The calculator uses the exact conversion.
How do I measure an awkward-shaped room?
Split it into rectangles and triangles, measure each one, and add the areas together.
These are estimates for planning and ordering. Materials, bag sizes and densities vary by product, so always check the figures on the packaging or with your supplier before you order. For structural work, follow the advice of a qualified builder or engineer.