Paint Coverage Calculator
How far will the paint you already have go? Enter the gallons on hand and the coats, pick the surface and finish, and see the square footage it covers as a range.
1 gallon = 3.79 litres. A 5-gallon bucket is the usual bulk buy.
What 1.00 gal covers in 1 coat
350–400 sq ft — 32.5–37.2 sq m
That is 3.8 L of paint at 350–400 sq ft per gallon for this surface and finish. The low end is what to plan on for thirsty, textured or masonry surfaces; the high end is for smooth, previously painted drywall. If your room is bigger than the high end, buy another gallon — running out mid-wall leaves a visible lap line.
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: Area covered = gallons × coverage (sq ft/gal) ÷ coats. Coverage comes from the surface and finish you picked — never a single fixed number.
How this estimate works: This is the paint calculator in reverse: instead of asking how much paint a room needs, it asks how far the paint you already have will go. Gallons are multiplied by the coverage range for your surface and finish, then divided by the number of coats. The range is the honest answer — the same gallon covers far less on rough masonry than on smooth drywall.
How the paint coverage calculator works
This is the paint calculator in reverse: instead of asking how much paint a room needs, it asks how far the paint you already have will go. Gallons are multiplied by the coverage range for your surface and finish, then divided by the number of coats. The range is the honest answer — the same gallon covers far less on rough masonry than on smooth drywall. If your room is bigger than the high end, buy another gallon: running out mid-wall leaves a visible lap line. Estimate — check the can label and current shelf price.
Try next: Paint Calculator · Paint Cost Calculator · Ceiling Paint Calculator
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