Paint Primer Calculator
How much primer for bare drywall, repainted walls, bare wood or masonry? Primer covers less than topcoat — pick the surface condition and brand and get gallons and cost as a range.
Primer for 400 sq ft (1 coat)
1.50–2.00 gal — 5.7–7.6 L
$26–$67 — estimated primer cost
Primer coverage is lower than topcoat coverage: 200–300 sq ft per gallon for this surface condition, at $17–$33 per gallon. Bare drywall and masonry soak up the most primer. Use a stain-blocking primer over water stains, smoke or knots — a standard primer will not seal them.
Estimate — check the can label and current shelf price. Coverage varies by brand, finish and surface, and prices vary by store and region. The range above is a planning figure, not a quote.
Formula used: Gallons = area × coats ÷ primer coverage (sq ft/gal for the surface condition), rounded up to the nearest quart. Cost = gallons × primer price per gallon for the brand and region.
How this estimate works: Primer coverage depends on how thirsty the surface is: new drywall and masonry absorb far more than a previously painted wall, so the coverage range shifts with the condition you pick. Price uses the brand's primer range (cheaper than its topcoat), adjusted for finish and region. One coat is enough for most priming; two are for stains, dark colours or bare wood.
How the paint primer calculator works
Primer coverage depends on how thirsty the surface is: new drywall and masonry absorb far more than a previously painted wall, so the coverage range shifts with the condition you pick. Price uses the brand's primer range, which is cheaper than its topcoat, adjusted for finish and region. One coat is enough for most priming; two are for stains, dark colours or bare wood. Use a stain-blocking primer over water stains, smoke or knots — a standard primer will not seal them. Estimate — check the can label and current shelf price.
Try next: Paint Calculator · Paint Cost Calculator · Ceiling Paint Calculator
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