Paint Calculator

How to estimate paint volume

1. Enter the net surface area receiving this paint. Exclude areas you will not paint and do not multiply by coats yet. Use floor area only when the floor itself is being painted.
2. Enter the product's coverage for one coat, select the matching unit and set the number of coats. The initial count of 1 is not a recommendation; follow the product instructions for your project.
3. Read the estimated volume in litres, US liquid gallons or Imperial gallons. Open Calculation details for the formula and one-coat amount. Choose container sizes separately; the result is not a can count.

Use compatible coverage and coat data

Paint volume equals net area multiplied by coats and divided by coverage per coat. Area and coverage are converted to compatible units first. Unrounded values determine the total, not the displayed one-coat amount.

Coverage here means area per volume for one coat, such as square metres per litre. If the label gives a range, choose an appropriate stated rate rather than entering the range. Lower coverage gives a larger estimate. Do not apply a multi-coat system's stated coverage and then multiply those coats again.

US liquid and Imperial gallons are different units. One US liquid gallon is 3.785411784 litres; one Imperial gallon is 4.54609 litres. Always check the coverage and result unit rather than assuming that an unqualified gallon means the same thing everywhere.

Calculate different products, coverage rates or coat counts separately. Primer and finish may not have the same yield. This estimator does not choose a coating system, infer mass-to-volume conversion or adjust for surface condition and application losses.

Worked paint estimates

For 50 square metres, coverage of 10 square metres per litre per coat and two coats, the estimate is 50 × 2 ÷ 10 = 10 litres. One coat with the same data would use 5 litres.

For 42 square metres, coverage of 11 square metres per litre per coat and two coats, the estimate is about 7.64 litres. This is a volume estimate, not an instruction to buy a particular can size.

For 700 square feet and two coats, coverage of 350 square feet per US liquid gallon gives 4 US gallons, or about 15.1 litres. The same numeric coverage per Imperial gallon instead gives 4 Imperial gallons, or about 18.2 litres.

An estimate, not guaranteed purchase quantity

Real use depends on the product, surface, application method and project conditions. Use suitable product data. No waste, touch-up allowance, automatic opening deduction, primer amount, price or container rounding is included.

Positive estimates display up to three significant digits; small nonzero quantities stay visible. The input limits are numerical bounds, not recommended project sizes, coverage rates or coat counts. No files or paint products are inspected.

Your measurements

The arithmetic runs in your browser. This tool adds no input upload, saved record or input-bearing URL. Existing website consent, analytics and network services remain separate.