Paint calculator
Enter room dimensions, number of doors and windows, and coats. Get gallons needed with a printable shopping list.
Material Totals
Door area 21 sq ft each, window area 15 sq ft each. Check your paint can for exact coverage rate.
Printable Shopping List
Generated by BuildTotals.com | buildtotals.com/tools/paint-calculator
Tips for estimating paint
Always buy one extra quart as a backup for touch-ups. Store it in a cool dry place - label the can with the room name and paint color code for future reference.
If the room walls are very dark or stained, budget for a coat of primer first (roughly half the gallons of the topcoat).
Frequently asked questions
How many gallons of paint do I need for a 12x12 room?
A 12x12 room with 8ft ceilings has about 384 sq ft of wall area. Subtract 2 doors (42 sq ft) and 2 windows (30 sq ft) = 312 sq ft. At 350 sq ft per gallon for 2 coats, you need about 2 gallons. The calculator above will trace this exactly.
How much does one gallon of paint cover?
Most interior paints cover 350-400 sq ft per coat. The calculator uses 350 sq ft/gallon as a conservative estimate. Check your specific paint can for the manufacturer rating.