Your result
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Enter your values, then click Calculate result.How this calculator helps
Estimate material before purchasing paint for a room or project. Use the paint manufacturer's coverage rate and the net wall area after subtracting large doors and windows for a more useful result.
How to use it
- 1
Measure net paintable wall or ceiling area in square feet.
- 2
Choose the required number of coats and use the coverage printed on the product tin.
- 3
Round up for the available container sizes and keep a small touch-up allowance.
Formula and methodology
Paint litres = wall area × number of coats ÷ coverage per litre. A practical purchase estimate then includes a small waste and touch-up allowance.
Uses measured dimensions and editable local rates for preliminary planning. It is not a bill of quantities, structural design or valuation.
Worked calculation example
For 1,000 square feet of net wall area, two coats and coverage of 120 square feet per litre, the base estimate is 16.7 litres before allowance.
How to interpret your result
Estimate paint litres and container count from wall area, coats and the product's stated coverage. Read the main result together with the supporting values rather than treating one number as a guarantee. The disclosed method is: Paint litres = wall area × number of coats ÷ coverage per litre. A practical purchase estimate then includes a small waste and touch-up allowance.
Input guide
Measure net paintable wall or ceiling area in square feet.
Choose the required number of coats and use the coverage printed on the product tin.
Round up for the available container sizes and keep a small touch-up allowance.
Scenario comparison
| Scenario | What it demonstrates |
|---|---|
| Worked baseline | For 1,000 square feet of net wall area, two coats and coverage of 120 square feet per litre, the base estimate is 16.7 litres before allowance. |
| Surface condition check | Porous, rough or newly plastered surfaces can absorb more paint. |
| Colour change stress test | Covering a dark colour with a light one may require extra coats or primer. |
Common mistakes to avoid
- Ignoring surface condition: Porous, rough or newly plastered surfaces can absorb more paint.
- Overlooking colour change: Covering a dark colour with a light one may require extra coats or primer.
- Failing to test application method: Spraying, rolling and brushing can have different waste rates.
Confirm dimensions on site and obtain an itemised quotation or measured bill of quantities from a qualified professional.
What can affect the result?
Surface condition
Porous, rough or newly plastered surfaces can absorb more paint.
Colour change
Covering a dark colour with a light one may require extra coats or primer.
Application method
Spraying, rolling and brushing can have different waste rates.
Limits of this estimate
The estimate cannot inspect surface porosity, application technique, paint thickness, openings or manufacturer-specific coverage conditions.
Sources and review information
Frequently asked questions
Is the paint quantity calculator free?＋
Yes. SolvePilot tools are free, work in your browser, and require no account.
Does SolvePilot store my values?＋
No. Calculations run locally in your browser and the values you enter are not sent to a server.
Should I treat the result as an exact bill or quotation?＋
No. Results are informed estimates. Final charges can vary because of taxes, tariffs, lender terms, usage patterns, or provider rules.
How can I improve the accuracy?＋
Use recent values from your own bill, statement or institution, review every assumption, and confirm important results with the relevant official source.
Should primer be included as a paint coat?＋
Calculate primer separately because its coverage and number of coats can differ from the finish paint.