Quick answer
Estimate how much surface a known quantity of paint can cover based on the manufacturer’s square-foot-per-gallon rating. Use the working RenoMetric calculator below for the actual estimate, then use this page to check assumptions, package rounding and project-specific considerations.
Open the working Paint calculator
Formula
Worked planning example
Two gallons rated at 375 ft² each provide about 750 single-coat ft², or about 375 ft² for two equal coats.
Common uses
- Checking leftover paint
- Comparing products
- Planning second coats
- Estimating small projects
How to get a better estimate
Measure the actual project rather than relying on listing dimensions. For irregular spaces, split the surface into simple measurable sections and add the results. Use the exact product label for package coverage, yield, density or square-foot coverage whenever it is available.
Keep waste and package rounding as separate steps. Waste covers cuts, breakage, pattern matching and unavoidable offcuts. Package rounding reflects the fact that many materials are sold only in complete bags, boxes, bundles or cans.
Before you buy: this page is a planning guide, not a contractor quotation or structural design. Verify final quantities with the product manufacturer, supplier or installer when project conditions could materially change the result.
Paint Coverage Calculator FAQ
Why does actual coverage vary?
Porosity, texture, color change, roller nap, spray loss and application thickness can all change practical coverage.
Can I rely on the maximum label coverage?
For purchasing, a conservative value within the manufacturer’s published range is often safer than assuming the maximum.
Does primer have the same coverage?
Not necessarily. Estimate primer using its own product label.