Room dimensions → how much material you'll need.
All dimensions in metres.
All dimensions in metres. Assumes a standard door (1.6 m²) and window (1.4 m²) per opening.
About this calculator
Flooring area is simply Length × Width, with a waste percentage added on top to cover offcuts.
Paint coverage starts from the total wall area (2 × (Length + Width) × Height), subtracts a standard allowance for doors and windows, then divides by your paint's coverage rate per litre, multiplied by however many coats you're applying.
Frequently asked questions
How much paint do I need for a room?
Work out the wall area, subtract doors and windows, then divide by the coverage figure on the tin and multiply by the number of coats. Most emulsions cover somewhere around 10-12 square metres per litre per coat.
How much extra flooring should I order for wastage?
Around 10% extra is the usual allowance for cuts and offcuts, rising to roughly 15% for diagonal or herringbone layouts and awkwardly shaped rooms.