How Much Paint for a 10x10 Room? (2026 Guide)
A 10x10 ft room with 8-ft walls has about 285 sq ft of paintable wall after doors and windows — two coats take about 2 gallons of paint. Add about 1 gallon to paint the ceiling, plus 1 gallon of primer for new drywall or a big color change.
How much paint a 10×10 room needs
A 10×10 room is easy to under-buy for: the floor is just 100 sq ft, but paint covers the walls, not the floor. With 8-ft walls the room carries about 320 sq ft of gross wall area; subtract a door (about 20 sq ft) and a window (about 15 sq ft) and you land on about 285 sq ft of net wall. At the standard 350 sq ft per gallon, two coats come to about 570 sq ft — which is why 2 gallons is the number most painters quote.
That 350 sq ft-per-gallon rate is the same assumption every paint label and calculator in this guide uses — see how many sq ft you get per gallon of paint for when texture, color or sheen change it. Here is the room scoped out:
| What you're painting | Area to cover | Gallons to buy |
|---|---|---|
| Walls only — two coats | 285 sq ft net walls (≈570 sq ft applied) | 2 gallons |
| Walls + ceiling — two coats each | 385 sq ft per coat (≈770 sq ft applied) | 3 gallons |
| Primer undercoat (new drywall or big color change) | 285 sq ft, one coat | 1 gallon |
Walls and ceiling together mean 285 + 100 = 385 sq ft per coat; two coats is 770 sq ft, and 770 ÷ 350 ≈ 2.2 — so the whole room rounds up to 3 gallons. You can also run the mix through the paint calculator and let it handle the rounding.
The math, step by step
Here is the full walk-through for a 10×10 room with an 8-ft ceiling, so you can recheck it on site:
- Wall area: perimeter of 40 ft (10 + 10 + 10 + 10) × 8-ft walls = 320 sq ft gross.
- Subtract openings: one door ≈ 20 sq ft + one window ≈ 15 sq ft = 35 sq ft, leaving 320 − 35 = 285 sq ft of net wall.
- Two coats of wall paint: 285 × 2 = 570 sq ft; 570 ÷ 350 ≈ 1.63 → buy 2 gallons.
- Ceiling (optional): 100 sq ft × 2 coats = 200 sq ft; 200 ÷ 350 ≈ 0.57 → buy 1 gallon if you paint it.
- Primer: one coat over 285 sq ft → 285 ÷ 350 ≈ 0.81 → buy 1 gallon for new drywall or a color change.
Paint is sold in whole gallons (or occasionally 5-gallon buckets), so always round up to the next can — leftover paint stores well for touch-ups.
Three checks before you buy
- Start from the net wall number. Measure wall length × height, then subtract every door and window opening; for a 10×10 room that baseline is about 285 sq ft, not the 320 sq ft of raw wall.
- Door frames, window frames and trim are counted separately. Baseboards, casing and the window sill in a room this size take well under a quart of trim paint, so none of that eats into the wall estimate above.
- Sand lightly between coats. A quick scuff with fine sandpaper and a dust-free wipe before the second coat gives the finish something to grip — it costs minutes and stops peeling later.
Sizing up or down? See how much paint a 12×14 bedroom needs, how much paint a living room takes, or for a workshop or garage, how much paint a 16×20 garage needs.
FAQ
How many gallons of paint do I need for a 10×10 room?
About 2 gallons of paint for two coats of wall paint. A 10×10 room with 8-ft walls has about 285 sq ft of net wall after a door (about 20 sq ft) and window (about 15 sq ft); two coats come to 570 sq ft, and at 350 sq ft per gallon that's 1.63 — so you round up to 2 gallons. Painting the ceiling adds about another gallon, and primer is separate.
How big is a 100 sq ft room?
10 ft by 10 ft — a standard small bedroom, nursery or home-office footprint. The floor and ceiling are each 100 sq ft; with 8-ft walls the four walls total about 320 sq ft before openings, or roughly 285 sq ft of net wall after a door and window.
Do you need primer for a 10×10 room?
Only for new drywall or a big color change. Unpainted drywall soaks up the first coat unevenly, and going from a dark color to a light one lets the old color show through — in both cases one coat of primer over about 285 sq ft takes about 1 gallon. Repainting the same tone over previously painted walls? Skip the primer and stick with the 2-gallon top-coat estimate.
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