Painting & Wall Calculators
Plan interior wall projects: paint for each coat and drywall or plasterboard sheets for walls and ceilings.
Paint Calculator
Gallons or litres of paint for a room, with doors and windows removed.
Open calculatorDrywall Calculator
Sheets of drywall or plasterboard for walls and ceilings.
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About these calculators
Paint quantities depend on the wall area, the number of coats and the coverage rate printed on the can. Coverage varies widely between products and surfaces: fresh plaster, bare drywall and strong colour changes all need more paint than a repaint in a similar colour.
Drywall (plasterboard in the UK and Australia) is bought by the sheet. Measuring the room perimeter, subtracting large openings and choosing the longest practical sheet length reduces joints, which saves taping and finishing time.
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