Paint Calculator
Calculate how much paint you need for a wall — enter dimensions, coats, and paint type.
How it works
- 1Enter the wall length and height in metres or feet using the Metric / Imperial toggle.
- 2Choose the number of coats and select your paint type to set the coverage rate (m²/L).
- 3The calculator applies litres = area × coats ÷ coverage and shows the result in litres and US gallons.
Use cases
- Estimating paint before a home renovation to avoid over- or under-buying.
- Comparing how much primer versus topcoat is needed for a fresh surface.
- Planning a masonry or exterior project where coverage rates differ from interior emulsion.
Frequently asked questions
How is paint volume calculated?
litres = (wall area in m²) × (number of coats) ÷ (coverage in m²/L). A 12 m × 2.5 m wall (30 m²) with 2 coats of emulsion (10 m²/L) needs 30 × 2 ÷ 10 = 6 litres.
What coverage rate should I use?
Emulsion/latex ≈ 10 m²/L, primer/undercoat ≈ 8 m²/L, gloss/enamel ≈ 12 m²/L, masonry ≈ 6 m²/L. Always check the tin for the manufacturer’s stated spread rate.
How do I convert litres to US gallons?
1 US gallon = 3.785 litres, so divide the litre result by 3.785. The calculator shows the US gallon figure automatically.
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