Free calculator
Paint Calculator
Estimate interior wall area, paint gallons and material cost from room dimensions, openings, coats and coverage.
Your project details
Change the assumptions below to match your project.
Planning estimate only. Actual contractor pricing varies with scope, access, code requirements, permits, labor availability, product brand, warranty and site conditions.
How many gallons of paint do you need?
The calculator estimates four-wall area, subtracts a simple allowance for doors and windows, multiplies by the number of coats, then divides by your paint’s stated coverage.
Remember primer and trim
Primer, ceilings, doors, baseboards and trim are not included in this wall-paint result. Textured or porous surfaces may also use more paint than the can’s nominal coverage.
Related painting planning guides
Interior painting cost per square foot · Cost to paint a room · How much paint do I need?