How Much Paint Do I Need? A Simple Way to Estimate

Running out of paint mid-wall is frustrating. Buying five extra gallons is expensive. Here's how to get it close to right.

Step 1: Measure the walls. Add up the length of every wall in the room, then multiply by the ceiling height. A 12 x 14 room with 8-foot ceilings is (12 + 14 + 12 + 14) x 8 = 416 square feet.

Step 2: Subtract doors and windows. Take off about 20 square feet per door and 15 per window.

Step 3: Divide by coverage. One gallon covers roughly 350–400 square feet per coat. Check the label on your can for the exact number.

Step 4: Plan for two coats. Most jobs need two coats for even color, especially when you're changing colors.

For that example room, you'd need a little over 2 gallons, so buy 2 gallons plus a quart, or 3 gallons if you want extra.

Tips

• Textured walls and dark colors can use more paint.
• We recommend Behr paint. Check the label for its coverage per gallon.
• Buy all your paint at once so the color matches from can to can.
• Keep leftovers for future touch-ups.

Bottom line: Measure, subtract, divide, and double for two coats.

← More painting tips  ·  Interior painting  ·  Exterior painting