Paint Calculator

Enter the room size. Doors and windows come off the wall area, and you can add the ceiling.

Room length ft

Room width ft

Wall height ft

Doors

Windows

Coats

Coverage sq ft per gallon

Paint the ceiling?

How it's figured

Wall area = room perimeter × wall height, minus about 21 sq ft per door and 15 sq ft per window. Gallons = area × coats ÷ coverage. Most wall paint covers 350–400 sq ft per gallon; use less for rough or porous surfaces or big color changes.

Want this for every job, all year?

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See the Interior Painting Estimator

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