How much extra paint should I buy?
Add about 10% for touch-ups, roller tray waste, and future patch jobs. The calculator includes a waste allowance you can adjust.
Interior Paint Calculator
Plan an interior repaint with default 350 sq ft per gallon and two coats. Toggle walls only, ceiling only, or both.
Rooms
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Project settings
Default 10% for touch-ups
$
Frequently asked questions
Can I calculate multiple rooms?
Yes. Add up to five rooms and the calculator totals paintable area, deductions, and gallons for the whole job.
Does this work for trim and doors?
This tool focuses on wall and ceiling area. Trim and doors use less paint — many DIYers buy a quart of trim paint separately.
Paint Calculator · https://paint-calculator.ca