How much does a gallon of paint cover?
Typical coverage for walls, ceilings and primer, and what makes it go up or down.
Last updated September 20, 2026
Most interior paint is sold with a coverage figure on the can, and that figure is the best number to use for your project. When you do not have the can yet, published guidance gives ranges. They vary a little between sources, and they depend mostly on the surface you are painting.
Typical coverage by surface
| Surface or product | Typical coverage (sq ft per gallon) | Notes |
|---|---|---|
| Smooth walls, previously painted | 350 to 400 | Retailers commonly give this range for one coat. |
| Textured walls | 300 to 350 | Texture increases the surface area, so paint goes less far. |
| New drywall or porous surfaces | 250 to 300 | Bare or porous surfaces absorb more paint, especially on the first coat. |
| Primer | 200 to 300 | Primer usually covers less area than paint. |
| Ceiling paint | 300 to 400 | One coat is usually enough unless there are stains. |
Sources: Lowe's, CalculatorSoup, RemodelCalculators and Caesar Cipher. Where sources disagree, the table shows the range they cover together.
What the paint calculator uses
The paint calculator offers four presets so you do not have to pick a number yourself: 400 for smooth, previously painted walls, 350 for typical walls (the default), 325 for textured walls, and 275 for new drywall or porous surfaces. If your can says something different, choose "My paint can says something else" and enter the figure from the label.
What changes coverage
- Surface texture. Rough or porous surfaces take more paint than smooth ones.
- Paint finish. Some manufacturers publish lower coverage for glossier finishes. One calculator lists 400 for flat, 350 for eggshell and satin, and 300 for semi-gloss and gloss, but figures differ by brand, so the label is the best guide.
- Color change. Covering a dark color with a light one takes more coats or a primer.
- How you apply it. Coverage figures assume a normal, even coat. Applying paint thickly uses more than the label suggests.
How to read the label on the can
Look for the coverage line, often written as "covers up to" a number of square feet per gallon. "Up to" figures describe good conditions, such as smooth, primed surfaces. If your walls are textured or bare, expect less. Buying a little extra is cheaper than running out partway through a wall.
Exterior surfaces
Exterior surfaces take paint differently. CalculatorSoup lists roughly 275 sq ft per gallon for wood siding, 200 for brick and 175 for stucco. The paint calculator on this site is built for interior rooms and does not cover exteriors.
Common questions
How many square feet does a gallon of paint cover?
On smooth walls, usually 350 to 400 square feet per coat. Textured, bare or porous surfaces cover less.
Does a gallon cover 400 square feet with two coats?
No. The coverage figure applies to one coat. Two coats use twice as much paint over the same area, so a gallon at 400 sq ft per coat covers about 200 sq ft with two coats.
How much does a gallon of primer cover?
Commonly 200 to 300 square feet, which is less than most paints.