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Paint Calculator

Calculate how many gallons of paint you need. Enter room dimensions or total area, and we'll account for doors, windows, coats, and surface type.

Coverage Rates by Surface Type

SurfaceCoverage (sq ft/gal)Notes
Interior Wall (smooth)350-400Standard latex on painted drywall
Interior Wall (textured)250-300Orange peel, knockdown, popcorn
Exterior Wood Siding300-350Smooth to rough-sawn
Stucco / Masonry150-200Very porous — use elastomeric paint
Ceiling350-400Flat paint recommended
Trim / Doors350-400Semi-gloss or satin
Deck / Fence200-300Stain or solid color

FAQ

How much does a gallon of paint cover?

A gallon of paint typically covers 350-400 square feet on smooth surfaces with one coat. Textured surfaces, bare drywall, and porous materials like stucco may only get 200-300 square feet per gallon. Always check the manufacturer's coverage rate on the can.

How many coats of paint do I need?

Most jobs require 2 coats for even coverage. You may need a separate primer coat when covering dark colors, painting new drywall, or switching between oil and latex paint. Some premium paints with built-in primer can cover in one thick coat.

How do I estimate paint for a room?

Measure the perimeter of the room (length + width x 2) and multiply by the wall height to get total wall area. Subtract 21 sq ft per door and 15 sq ft per window. Divide by the coverage rate (usually 350-400 sq ft/gallon) and multiply by the number of coats.

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