Home Improvement
Flooring Calculator
Estimate base room area, a selected waste allowance, and total flooring square footage.
Paint Calculator
Estimate wall area, multi-coat coverage, exact gallons, and a rounded-up paint purchase quantity.
Measure walls before buying paint and subtract only openings you do not intend to coat.
Enter your details
Wall and paint details
Gross wall areaPaintable areaCoverage for all coatsExact estimateRounded-up purchase quantity
Your estimate will appear here
Complete the fields and calculate to see a detailed result.
Planning paint quantity
This estimate separates gross wall area from paintable area, then accounts for every coat.
Formula and methodology
Gross area = wall length × wall height × similar walls. Subtract excluded area, multiply by coats, then divide by the selected paint's coverage per gallon.
Worked example
Four 12 ft by 8 ft walls have 384 sq ft gross area. Excluding 40 sq ft and applying two coats requires 688 sq ft-coats. At 350 sq ft per gallon, 1.97 gallons rounds up to 2 whole gallons.
Assumptions and limitations
Porosity, texture, color change, primer, application loss, and manufacturer specifications affect coverage.
Frequently asked questions
Why round gallons up?
Whole-gallon containers may be needed; check available sizes.
Is label coverage guaranteed?
No. Surface and application conditions change coverage.
What should I exclude?
Exclude only measured surfaces that will not receive this paint.
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