Paint calculator

Metric Paint Calculator

Room length (m)Measure the longer wall, in metres.Room width (m)Measure the shorter wall, in metres.Wall height (m)Floor to ceiling height.Number of coatsUse whole coats only.Paint coverage (m2/L)Use the product label coverage.Waste percent (%)Allows for touch-ups and surface variation.Door/window opening area (m2)Optional area to subtract from the walls.Container size (litres)Containers are rounded up.Price per container (optional)Used only to multiply whole containers by your entered price.

Estimate

Enter measurements and calculate to see the paint estimate.

Formulas and assumptions

Gross wall area = 2 x (length + width) x height.
Net wall area = gross wall area - door/window opening area.
Litres before waste = net wall area x coats / coverage.
Waste is applied after the base litre calculation.
Application method, surface condition, colour change, and product coverage can change actual paint needed.

Planning estimate only. Not engineering, structural, legal, installation, or supplier advice. Check measurements, site conditions, and product labels before buying or building. This paint estimate uses the coverage and container size entered on this page.

Plan before you buy

Measure with clarity.

Start with the calculator that matches your project. Inputs and estimates stay in your browser.

Browse calculators ↗

Plan Buy Build

Metric-first material estimates for practical home projects. No accounts, tracking, supplier price feeds, or hidden assumptions.

Calculators

Paint calculator
Flooring calculator
Tile calculator
Concrete calculator
Gravel, soil & mulch calculator

Guides

How to Measure a Room for Paint
How to Calculate Flooring Waste
How to Measure for Floor and Wall Tiles
All guides

Information

About
Privacy
Disclaimer

Check measurements, product labels, and site conditions before buying or building.