Paint Coverage Calculator
Estimate wall area, paint required, cans needed, and paint cost for a room or project.
Paint Coverage, Coats, and Project Cost Explained
A Paint Coverage Calculator estimates how much paint you need for walls or a room by using wall area, doors, windows, number of coats, paint coverage rate, and waste allowance. It can also estimate paint cost when you enter a price per can.
Paint planning is more accurate when you separate surface area from coverage. A room with large windows or doors may need less paint, while textured walls, dark color changes, new drywall, and multiple coats can increase the amount required.
Measure Wall Area
Wall area is estimated from room perimeter multiplied by wall height. Doors and windows are subtracted because they usually do not need wall paint, although trim and frames may be separate projects.
Coats Change Quantity
Most projects need two coats for even coverage, especially when changing colors. Primer, dark colors, porous walls, and rough surfaces can increase total paint needs.
Coverage Per Can
Paint labels often list coverage per gallon or liter. The calculator divides the total paintable area by that coverage rate, then rounds up to the number of cans needed.
Estimate Project Cost
When you enter the price per can, the calculator estimates paint cost before supplies. Brushes, rollers, trays, tape, primer, drop cloths, and labor are not included unless you add them separately.