Painting Calculators & Guides

Accurate paint gallon calculators with coat multipliers, primer needs, door/window deductions, and coverage factors from standard 350-400 sq ft per gallon.

Calculators

  • Interior Paint Calculator — Calculate gallons of paint needed for room walls, factoring in length, width, height, coats, and window/door deductions.
  • Exterior Paint Calculator — Estimate gallons of 100% acrylic exterior paint and primer needed for home siding, trim, and gables.
  • Ceiling Paint Calculator — Calculate flat ceiling paint gallons based on room dimensions, ceiling texture, and light reflection requirements.
  • Primer Calculator — Calculate gallons of PVA or stain-blocking primer for new drywall, bare wood, or dramatic color changes.
  • Trim and Baseboard Paint Calculator — Calculate quarts or gallons of semi-gloss or enamel paint for baseboards, crown molding, door casings, and chair rails.
  • Door Paint Calculator — Estimate paint quarts or gallons needed for interior or exterior doors, factoring in paneled vs slab surfaces and casing jambs.
  • Cabinet Paint Calculator — Calculate primer and specialized cabinet enamel gallons needed for kitchen and bathroom cabinets, doors, and drawers.
  • Wallpaper Roll Calculator — Calculate how many single or double rolls of wallpaper are needed for room walls, factoring in pattern repeat waste.

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