Paint for a job
Enter total wall area and coats. Result rounds up to whole units.
sq ft
m²
Gallons
-gal
Quarts (approx)
-qt
gallons = area × coats ÷ 375 (about 350 to 400 sq ft per gallon, one coat)
Litres
-L
litres = area × coats ÷ 9 (about 8 to 10 m² per litre, one coat)
Estimate only. Rounded up with a 5 percent waste allowance. Confirm the final quantity with your supplier before ordering.
How the paint estimate works
One US gallon of interior latex covers about 350 to 400 square feet in a single coat, so we use 375 as a working average. Primer and dark or uneven colours can need more. Subtract large openings like garage doors from the wall area, but it is fine to leave normal doors and windows in as a built in buffer.
Painting a room? A complete roller, tray and brush kit covers most interior jobs.
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Common questions
How much paint do I need for a 12 by 12 room?
A 12 by 12 room with 8 foot walls has about 384 square feet of wall. At two coats that is roughly 2 gallons.
How many square feet does a gallon of paint cover?
About 350 to 400 square feet per coat for typical interior latex. Rough or porous surfaces and primer coats reduce coverage.
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