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How to Use Our Paint Calculator

3 min read

How to Use Our Paint Calculator

Buying the wrong amount of paint means either extra trips to the store or wasted money on unused gallons. Our Paint Calculator eliminates the guesswork.

Entering Your Room Details

  • Room Length and Width -- The dimensions of the room you are painting.
  • Wall Height -- Standard ceiling height is 8 feet, but measure yours to be sure.
  • Number of Doors -- Standard doors are roughly 21 square feet. The calculator deducts this from the paintable area.
  • Number of Windows -- Average windows are roughly 15 square feet each.
  • Number of Coats -- Most paint jobs require 2 coats. Use 1 coat for touch-ups or when painting a similar color over a similar color. Use 3 coats when covering dark colors with light ones.

Reading Your Results

Total Wall Area -- The total square footage of your walls minus doors and windows.

Gallons Needed -- One gallon of paint covers approximately 350-400 square feet per coat. The calculator accounts for this coverage rate and the number of coats you selected.

Tips for Accuracy

Buy all your paint at once. Even the same color can vary slightly between batches. Buying everything in one trip ensures consistent color.

Round up. Always round up to the next full gallon. Having leftover paint is useful for future touch-ups.

Textured walls need more paint. Heavy texture can reduce coverage by 20-30%. If your walls are textured, add an extra 25% to the calculated amount.

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