How much paint for a 16 × 20 room?
A 16x20 room with 8-foot ceilings has about 540 sq ft of paintable wall after a typical door and window. Two coats takes 3.09 gallons.
| Coats | 8 ft ceilings | 9 ft ceilings |
|---|---|---|
| 1 coat | 1.54 gal | 1.75 gal |
| 2 coats (recommended) | 3.09 gal | 3.5 gal |
| 3 coats (drastic color change) | 4.63 gal | 5.25 gal |
Estimates are for planning. Confirm quantities against your measured site and product packaging before ordering, and follow local building codes.
Buying paint for a 16x20 room without waste
Round up to whole gallons only when you're close to the line; quarts cover about 90 sq ft per coat and are the cheaper top-up for small gaps. Manufacturer coverage assumes smooth, primed walls: textured or bare drywall drinks 15 to 25 percent more, which is exactly when the full paint calculator's coats setting earns its keep. For what the whole job costs with labor, see painting a room: DIY vs. hiring, and the whole-house budgeting view on our sister site: interior painting costs.
Frequently asked questions
How much paint do I need for a 16x20 room?
For walls with 8-foot ceilings: about 1.54 gallons for one coat or 3.09 gallons for the recommended two coats, after subtracting a typical door and window. Most people buy 4 gallons and keep the remainder for touch-ups.
How much paint for the ceiling of a 16x20 room?
The ceiling is 320 sq ft, which needs about 0.91 gallons per coat at standard 350 sq ft per gallon coverage. Ceilings usually take one coat of flat ceiling paint unless you're covering stains or a color.
Is one gallon enough for a 16x20 room?
No. Two coats on the walls of a 16x20 room takes about 3.09 gallons, so one gallon covers only 32% of the job.