To find your magic number, use this step-by-step calculation:
Divide your final number by 350 (for a conservative estimate) or 400 (for smooth walls). Surface Type Coverage per Gallon Smooth Walls 350 - 400 sq. ft. Textured Walls 250 - 300 sq. ft. Primer 200 - 300 sq. ft. Trim/Moulding ~550 sq. ft. 💡 Pro Tips for Better Estimates Paint Calculator | Estimate How Much Paint You'll Need sherwin williams how much paint to buy
Multiply that perimeter by the wall height. To find your magic number, use this step-by-step
Deduct 21 sq. ft. per door and 15 sq. ft. per window . Textured Walls 250 - 300 sq
Add the length of all four walls together.
Estimating paint is more than just guessing—it's a math problem that saves you from unnecessary trips back to the store. For Sherwin-Williams products, a single gallon typically covers on smooth, previously painted surfaces . 🎨 The "Golden Formula" for Rooms