Enter the length and width of the room and choose a smooth or textured ceiling. The calculator works out the ceiling area, multiplies by the number of coats and divides by the coverage of ceiling paint, then rounds to gallons and quarts.
How the ceiling paint calculator works
- Area = length × width of the room.
- Paint = area × coats ÷ coverage, plus the extra percentage.
- Coverage is 300 sq ft per gallon for a smooth ceiling and 200 sq ft per gallon for a textured or popcorn ceiling, which holds more paint.
BEHR Premium Plus Ceiling Flat lists 250 to 400 sq ft per gallon, and Glidden Professional Ceiling Paint lists 200 to 300 sq ft per gallon, depending on the surface and how the paint is applied. The calculator uses 300 where the two ranges overlap, and the low end for textured ceilings.
Ceiling paint coverage by product
| Ceiling paint | Coverage per gallon |
|---|---|
| BEHR Premium Plus Interior Ceiling Flat | 250 to 400 sq ft |
| Glidden Professional Ceiling Paint | 200 to 300 sq ft |
Worked example
A 12 × 16 ft living room has a 192 sq ft ceiling. Two coats on a smooth ceiling at 300 sq ft per gallon, plus 10% extra, is 192 × 2 ÷ 300 × 1.1 = 1.41 gallons: one gallon and two quarts, or two gallons. If the ceiling is textured, at 200 sq ft per gallon it is 2.11 gallons, so two gallons and a quart.
Ceiling paint for common room sizes
| Room | Ceiling area | Smooth (300 sq ft/gal) | Textured (200 sq ft/gal) |
|---|---|---|---|
| 10 × 10 ft | 100 sq ft | 0.73 gal | 1.10 gal |
| 12 × 12 ft | 144 sq ft | 1.06 gal | 1.58 gal |
| 12 × 16 ft | 192 sq ft | 1.41 gal | 2.11 gal |
| 14 × 20 ft | 280 sq ft | 2.05 gal | 3.08 gal |
| 20 × 20 ft | 400 sq ft | 2.93 gal | 4.40 gal |
Painting a ceiling
- Flat white ceiling paint hides roller marks and small flaws better than glossier finishes.
- Paint the ceiling before the walls so drips and cut-in lines land on surfaces you have not painted yet.
- Use an extension pole and roll in the direction of the main light source to hide lap marks.
- Popcorn ceilings can loosen when wet. Test a small area and use a thick-nap roller.
Step by step: estimating and painting a ceiling
Tips before you buy
- New drywall ceilings need primer first; the primer calculator can include the ceiling.
- For the walls, use the paint calculator.
- Ceiling paint that goes on tinted and dries white makes it easier to see missed spots.
- See paint coverage per gallon for how surface and color change affect coverage.
