Paint Calculator
Estimate gallons of paint for any room — doors and windows subtracted.
Gallons
1.81
Buy the next whole gallon
Paintable area
316 ft²
Total wall area
352 ft²
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How does the paint calculator work?
Wall area is the room perimeter × ceiling height. Subtract roughly 21 ft² per door and 15 ft² per average window, then multiply by the number of coats and divide by 350 ft²/gallon.
Formula: gallons = ((2(L+W) × H − doors×21 − windows×15) × coats) ÷ 350
What do people use the paint calculator for?
Paint for a Bedroom
Estimate gallons of paint for any bedroom.
Paint for a Living Room
Estimate gallons of paint for a living room.
Paint for a House Exterior
Estimate gallons of exterior paint for siding and trim.
Paint for a Ceiling
Estimate gallons of paint for any ceiling.
Paint for Cabinets
Estimate quarts and gallons for a kitchen cabinet repaint.
What else do people ask about this calculator?
How much paint do I need for a 12×12 room?
A 12×12 room with 8 ft ceilings, 1 door and 1 window needs about 2 gallons for two coats.
How much does a gallon of paint cover?
About 350 ft² per gallon on smooth interior walls. Textured or porous surfaces reduce coverage to 250–300 ft².
Which related calculators should I use next?
Where can I learn more about these materials?
Weights, coverage, types and buying tips for the materials this calculator estimates.
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