Standing at the paint counter — Home Depot, a Benjamin Moore dealer, Sherwin-Williams, Cloverdale, Canadian Tire — the question is always: how many gallons? This calculator turns your room dimensions into a gallon count using the Coverage line on the can you bought.
Default 10% for touch-ups
Gallons first, then tools. Short answers you can use in the aisle — tap a card for the full how-to.
9-inch frame + 3/8″ nap for smooth walls. Go 1/2–3/4″ nap on texture.
One 2–2½″ angled sash brush for cutting in. Skip cheap foam for walls.
Both. Canvas (or taped plastic) on floors. Painter’s tape on trim and glass.
Ceiling first, then walls, then trim last.
Two finish coats on walls for most colour changes. Primer first on new drywall or stains.
Tray + liners, extension pole, stir stick, sandpaper, putty knife, TSP substitute.
12×12 room, 8 ft ceilings, walls only ≈ 384 sq ft. Two coats at 400 sq ft/gallon = 768 ÷ 400 ≈ 1.9 gallons — buy 2 gallons if walls are smooth and primed. Texture or a big colour change? Use 350 sq ft/gallon and buy 3.
That 400 sq ft/gallon figure is typical of Behr Premium Plus, Benjamin Moore Regal Select, Dulux Diamond, Cloverdale interiors, and similar lines — but your can wins. 10×12 bedroom with two doors and one window: deduct openings, keep two coats, expect roughly 2 gallons.
For coverage-only math (sq ft ÷ label rate), use the paint coverage calculator. Brand-specific pages: Benjamin Moore, Sherwin-Williams, Cloverdale, Dulux. Full chart: paint coverage by brand in Canada.
Running short mid-project means a second trip to the store — and the new can may not match the first batch exactly. Buying too much leaves sealed gallons in the garage for years.
Enter your exact dimensions above for your project. The quick answer box uses a typical Canadian DIY room so you have a starting point before you measure.
New drywall, water stains, or a jump from navy to white usually needs primer first. Primer often covers less area per gallon than finish paint — check the label and run the calculator once per product.
If you are only refreshing the same colour on sound walls, one coat may be enough. Our how many coats guide walks through when two coats are non-negotiable.
Coverage on Canadian cans is listed in square feet per litre or per gallon depending on the brand. Benjamin Moore, Sherwin-Williams, Cloverdale, Dulux, Sico, Beauti-Tone, CIL, Valspar, and Behr all print coverage on the back — enter that number in project settings.
Flat and ceiling paints often cover more than high-gloss trim. Textured walls and deep colours cover less — the 10% waste setting helps, but add extra for orange peel or knockdown texture.
A 12×12 room with 8 ft ceilings has about 384 sq ft of wall area. With two coats and 350 sq ft per gallon coverage, you need roughly 2.2 gallons — buy 3 gallons to be safe.
Most interior latex covers 350–400 sq ft per gallon on smooth walls. Check your can — flat and textured surfaces cover less.
New drywall, stains, or bold color changes usually need primer first. Run the calculator twice — once for primer, once for topcoat — or switch paint type in settings.
Most interior latex covers 350–400 sq ft per gallon on smooth, primed walls. Behr Premium Plus, Benjamin Moore Regal Select, Dulux Diamond, and similar lines often list up to ~400 sq ft/gallon — enter your exact label number in project settings.
Yes. Coverage is printed on every Canadian can. Use this page for a shopping-list gallon count, or open the brand calculator that matches your lid: Behr, Benjamin Moore, Sherwin-Williams, Cloverdale, Dulux, Sico, Beauti-Tone, CIL, or Valspar. We are not affiliated with any of them.
Brand names appear only so you can match typical Canadian label coverage. Paint Calculator is an independent tool — not affiliated with, endorsed by, or sponsored by Behr, Benjamin Moore, Sherwin-Williams, Cloverdale Paint, Dulux, Sico, Beauti-Tone, CIL, Valspar, PPG, The Home Depot, Lowe’s, Canadian Tire, Home Hardware, or their parent companies. Always use the Coverage figure printed on your can. Full disclaimer.
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