Plan your project
Paint calculator
Estimate wall and ceiling paint, subtract door and window areas, and calculate paint costs.
How it works
From room dimensions to paint quantity
Net walls = 2 × (length + width) × height − openings
Ceiling = length × width (if selected)
Paint = (net walls + ceiling) × coats ÷ coverage
All four walls are assumed to have the same height. Opening area is subtracted once, before applying coats. For multiple rooms, calculate each separately and add the quantities. If ceiling paint differs, estimate it separately instead of enabling the ceiling option.
Worked example
A 4 × 3 m room, 2.7 m high
Gross wall area is 37.8 m². Subtract 4 m² of doors and windows to get 33.8 m². Two coats at 10 m² per litre need 6.76 litres. At ₹300 per litre, the proportional material estimate is ₹2,028, before rounding up to container sizes.
One US gallon equals 3.785411784 litres. Imperial/UK gallons are not used. Coverage is always for one coat; check your manufacturer’s label rather than assuming the sample value applies to your paint.
Calculations run in your browser. Optional currency conversion contacts Frankfurter for rates; your measurements and cost amounts are not sent. Reference rates are not bank quotes.