Paint calculator: how much paint do I need?
Work out exactly how many gallons (or quarts) to buy for a room or a piece of furniture — doors, windows, coats and primer included.
You'll need about
Estimates assume standard doors (20 sq ft) and windows (15 sq ft). Always check the coverage on your paint can — and buy from one batch so the color matches.
How the paint calculator works
For walls, we add up the perimeter of the room, multiply by wall height, then subtract about 20 square feet for each standard door and 15 square feet for each window. That paintable area is multiplied by the number of coats and divided by your paint's coverage — most interior paints cover 350–400 square feet per gallon on smooth walls, less on texture or fresh drywall.
For furniture, we use typical paintable surface areas (a six-drawer dresser is around 50 square feet with drawer fronts and sides) and a coverage of about 150 square feet per quart, which is typical for chalk-style furniture paints. We round up and add a little extra for touch-ups.
Tips for buying the right amount
- Buy all your paint at once from the same batch so the color matches.
- Dark or bold colors over light walls often need a tinted primer or a third coat.
- Keep a labeled jar of leftover paint for future touch-ups.
Picking the color is the fun part — try our color palette generator or read how to choose paint colors. Painting furniture? Start with how to paint furniture with chalk paint.
FAQ
How much paint do I need for a 12x12 room?
A 12x12 room with 8-foot walls, one door and two windows has roughly 330 square feet of wall. Two coats need about 1.75–2 gallons depending on texture.
How many coats of paint should I use?
Two coats is standard for an even finish. One coat can work for a refresh in the same color; three may be needed for big color changes without primer.
How much paint does a dresser take?
Most six-drawer dressers need about one quart of chalk-style paint for two coats; larger buffets may need two quarts.
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