Wall Paint Quantity Calculator
Litres for walls & ceiling by coats and coverage class.
Fresh plaster drinks the first coat — prime first or budget 30% extra. 'Coverage' on the tin is ideal-lab smoothness; real walls run 15–20% worse.
Formula
Wall Paint Quantity Calculator is a free paint calculator for civil engineers, contractors and quantity surveyors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Wall Paint Quantity Calculator
Litres for walls & ceiling by coats and coverage class. The calculation implements L = area × coats / coverage × 1.1 (Paint manufacturer datasheets). Fresh plaster drinks the first coat — prime first or budget 30% extra. 'Coverage' on the tin is ideal-lab smoothness; real walls run 15–20% worse.
How to use Wall Paint Quantity Calculator
- 1Enter Paintable area in m² (≈ wall perimeter×height − openings; rooms ≈ 3.5× floor area).
- 2Enter Coats.
- 3Enter Coverage per coat in m²/L (Emulsion on plaster 11–14 · primer 10–12 · textured 4–6).
- 4Read Paint needed, Suggest 1L/4L/10L cans instantly — no submit button needed.
- 5Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Wall Paint Quantity Calculator?
- ✓Implements the standard formula — L = area × coats / coverage × 1.1
- ✓Reference cited on-page: Paint manufacturer datasheets
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Wall Paint Quantity Calculator use?+
It computes L = area × coats / coverage × 1.1, per Paint manufacturer datasheets. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Fresh plaster drinks the first coat — prime first or budget 30% extra. 'Coverage' on the tin is ideal-lab smoothness; real walls run 15–20% worse.
Does it include wastage?+
Yes — standard wastage/bulking factors are built in and stated in the formula line, so the quantity is an orderable number, not a bare geometric volume.
Is the Wall Paint Quantity Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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