Paint Calculator

Estimate paintable area, opening deductions, coats, label coverage, containers, and a rough cost for walls, ceilings, fences, and trim.

Paint Inputs

Price field
Leave the price blank if you only want the volume and container estimate.
Room and ceiling modes use room dimensions. Wall, fence, exterior-wall, and trim modes use surface length and surface height. Deduction area is optional and can stand in for doors, windows, or skipped sections.

Paintable area becomes coated area

The first calculation is the surface you intend to paint after large opening deductions. Coats then multiply that area: two coats cover twice the paintable area. Coverage turns the coated area into litres or gallons, and container size turns that volume into a purchase quantity.

Paint calculation

gross wall area − openings = paintable areapaintable area × coats ÷ label coverage = paint volume

Use the product label, not a generic coverage claim

Coverage varies with product, surface texture, roller or spray method, colour change, and porosity. Enter the coverage printed for the coating you plan to use. Primer, ceiling paint, trim paint, and topcoat are separate material decisions.

One coat versus two

For the same wall, two coats double the coated area. If a room has 31.8 m² of paintable wall area, one coat uses 31.8 m² of coverage; two coats use 63.6 m². The result breakdown makes that change visible before you choose tin sizes.

Plan a paint purchase with context