Price RangerPainting
How much paint for a room
Last reviewed 2026-10-20. Estimates, not legal or tax advice.
Net square feet times coats, divided by the coverage on the can, rounded up, is the gallons. A typical can is about 350 square feet per coat. Check the can you will actually buy.
Steps
- Measure the walls.
- Subtract doors and windows.
- Multiply by the number of coats.
- Divide by the coverage on the product you will use.
- Round up. A partial gallon is still a gallon to buy.
320 square feet of wall
320 square feet of wall, minus one door and one window, is 287.6 square feet to paint.
2 coats at 350 square feet per gallon is 2 gallons.
Price the gallons, the prep, and the hours separately. Coverage on the can is a starting point, not a bid.
Easy to miss
- Buying from the room's floor size instead of the wall size.
- Ignoring a color change that needs another coat.
- Forgetting primer and then treating it as free.
Further reading
- Renovation, Repair and Painting Program
U.S. EPA
Pre-1978 paint work can require lead-safe practices, and that prep belongs on the quote.
- Manage your finances
U.S. Small Business Administration
A plain official walkthrough of keeping the money you charge separate from what the job costs you.
- Contractors State License Board
California CSLB
California's license board states which jobs need a contractor license before you price them.