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CCalculateWise

Home & Property

Paint Calculator

Estimate paint gallons and cost for a room, accounting for doors, windows and coats.

CalculateWise provides estimates for informational purposes only and is not financial, tax, legal, lending or investment advice.

How to use the Paint Calculator

  1. Enter room length, width and height.
  2. Enter the number of doors and windows.
  3. Set coats, coverage and price per gallon.

How it works

Wall area is reduced by standard door and window sizes, then divided by coverage per gallon and coats.

Formula

Gallons = paintable area × coats ÷ coverage per gallon

Example

A 12×10 ft room with 8 ft ceilings, one door, one window and two coats at 350 sq ft/gallon needs about 2 gallons.

Common uses

  • Room makeovers
  • Rental turnovers
  • Budgeting supplies

Frequently asked questions