How much paint do I need?
Enter the room and how you want it painted. The answer comes in cans you can actually buy, rounded up so you do not run out halfway down the last wall.
Wall paint to buy
2 gallons
334 sq ft of wall, 2 coats
Walls
1.9 gal
2 gallons
Ceiling
—
not included
Trim and doors
2 quarts
semi-gloss, two coats
Before you buy
- Worked at 350 sq ft per gallon per coat, the low end of most labels, so there is a little left for touch-ups.
- Buy all the wall paint for one room in one go, or have the store box it (mix the cans together), so the colour matches from wall to wall.
- Textured walls (orange-peel or knockdown) and bare drywall soak up more. Add about 10 to 15 percent for those.
- Keep a labelled quart of leftover paint for touch-ups later.
Before anyone sands
- Homes built before 1978 may have lead paint. Do not sand or scrape old paint until it has been tested.
- A ceiling stain means there was a leak. Make sure the leak has been fixed, then seal the stain with a stain-blocking primer.
Rather not spend the weekend on a ladder? A handyman can prep and paint the room. Free estimate.
How this works
Wall area is the room's perimeter times the ceiling height, less a standard allowance for each door and window. That area times the number of coats, divided by the coverage of a gallon, is the paint to buy.
Coverage is taken at 350 square feet per gallon per coat, the low end of what most paint labels state for smooth walls, so there is a little left for touch-ups. Trim is worked out from the baseboard length and the door and window casings.
It runs in your browser and nothing you enter is sent anywhere. It is a guide, not a quote or a professional assessment — products and walls differ, so follow the maker's instructions where they disagree, and the handyman confirms what the job needs when they see it.
Questions people ask
- How much does a gallon of paint cover?
- Most interior paints state 350 to 400 square feet per gallon per coat on smooth, primed walls. Textured walls and bare drywall take more.
- How many coats of paint does a room need?
- Two coats is the usual answer and gives even colour. One coat can be enough when refreshing the same colour over sound paint; a dramatic colour change can need a third coat or a primer first.
- How much paint do I need for a 12 by 12 room?
- With 8-foot ceilings, one door, two windows and two coats, about 2 gallons for the walls. Use the calculator for your own room.
- Do I need primer before painting?
- Over new drywall or patches, water stains, glossy old paint, or a big change from dark to light, yes. Over clean paint of a similar colour, usually not.
Other free tools
Rather have someone look at it?
Phones answered around the clock. Free estimate — the price is agreed before work starts.