Paint Coverage Calculator
Get the exact number of paint gallons for your room. Uses Sherwin-Williams and Benjamin Moore published coverage rates, with adjustments for primer, ceilings, and number of coats.
Paint Coverage Rates by Type
Coverage rates published on the technical data sheets of major US paint manufacturers. Use the low end of the range for rough or porous surfaces, and the high end for smooth, primed drywall.
| Paint Type | Coverage | Recommended Coats | Notes |
|---|---|---|---|
| Interior Wall Paint (acrylic/latex) | 350–400 sq ft / gallon | 2 coats | Standard interior wall coverage on primed, smooth drywall. |
| Ceiling Paint (flat) | 350–400 sq ft / gallon | 2 coats | — |
| Primer (interior) | 300–400 sq ft / gallon | 1 coat | Use a tinted primer over dark colors or stains. |
| Exterior Wall Paint | 250–400 sq ft / gallon | 2 coats | Rough surfaces (stucco, brick) sit at the low end. |
| Trim & Door Enamel | 300–400 sq ft / gallon | 2 coats | — |
Choosing the Right Finish
Sheen level determines how durable and washable the painted surface will be — and how forgiving it is of wall imperfections.
| Finish | Sheen Level | Best For |
|---|---|---|
| Flat / Matte | 0–5% gloss | Ceilings, low-traffic walls, hiding wall imperfections. |
| Eggshell | 10–25% gloss | Living rooms, bedrooms; light cleanability. |
| Satin | 25–35% gloss | Kitchens, kids’ rooms, bathrooms — wipes clean. |
| Semi-Gloss | 35–70% gloss | Trim, doors, cabinets, bathrooms — durable & washable. |
| High-Gloss | 70%+ gloss | Front doors, accent furniture — most durable, shows imperfections. |
Painting Pro Tips
Buy single batch
When buying multiple gallons of the same color, ask the store to mix all cans from the same batch number. Cans mixed at different times can have visible color variation.
Paint ceiling first
Always paint top-down: ceiling, walls, trim. Drips and roller splatter fall onto unfinished surfaces, so you cover them later anyway.
Cut in before rolling
Use a 2.5-inch angled brush to paint a 3-inch band along ceiling, baseboards, and corners before you roll. Roll wet-into-wet to hide brush marks.
Account for textured walls
Orange peel and knockdown textures increase surface area by 10–30%. Multiply your gallon count by 1.15 for light texture, 1.3 for heavy texture.
Frequently Asked Questions
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Sources
The figures on this page are based on data from these authoritative industry sources.
- Sherwin-Williams Technical Data — Paint coverage rates per gallon from the manufacturer’s product data sheets.
- Benjamin Moore Technical Data — Paint coverage rates per gallon from the manufacturer’s product data sheets.