Calculate interior wall and ceiling paint litres from metric room dimensions. Compare coverage scenarios and find the lowest-cost mix of two entered tin sizes.
How much paint do I need for one room?
Measure the walls and optional ceiling, subtract doors and windows, then multiply the paintable area by coats and waste allowance before dividing by the product-label coverage. The result is converted into a purchasable two-size tin mix.
How this calculator works
Required litres = paintable area × coats × (1 + waste) ÷ product coverage. The calculator checks sufficient combinations of the two entered tin sizes and chooses lowest cost, then least surplus, then fewest tins; the exact product data sheet controls.
How this page was produced
Curatevia converted the listed official or first-party source rules into deterministic local calculations, then checked reference, boundary, invalid and bilingual-equivalence cases.
Limits and safe next step
Product data sheets, surface condition and the painter's inspection override this planning estimate.
Sources accessed 6 August 2026. Review the official source links before relying on a regulated decision.
