How much area will the paint cover?
Multiply gallons by the product coverage per gallon. For two coats, divide that area by 2. Texture, porosity, overspray, and touchups reduce usable coverage.
One coat vs two coats
A gallon rated for 350 sq ft covers about 350 sq ft for one coat, or about 175 sq ft for two coats before waste. Primer, dark color changes, and rough surfaces can change that.
Use label coverage first
Paint, stain, masonry coating, spray paint, and specialty coatings can have very different coverage. The product label is the best input for final buying.
Stain and sealer coverage examples
Examples use broad planning coverage. Rough, dry, or weathered wood may need more stain or sealer.
| Surface | Measured area | Estimated gallons |
|---|---|---|
| Deck boards | 300 sq ft | 2 gallons |
| Deck rails | 220 sq ft | 2 gallons |
| Fence face | 600 sq ft | 3 gallons |
| Wood siding | 1,200 sq ft | 6 gallons |
Before you calculate
- Measure boards, rails, posts, stairs, siding, pergolas, and fence faces separately.
- Use lower coverage for rough, dry, weathered, or very porous wood.
- Check whether the product coverage is for one coat or the full recommended system.
Common mistakes
- Using deck floor area only when rails, stairs, or posts are also being stained.
- Ignoring wood porosity, sanding, previous coatings, or second coats.
- Combining transparent stain, solid stain, and sealer under one coverage number.
Formula
covered sq ft = (paintVolume * coveragePerGallon) / coats / (1 + wastePercent / 100)
Assumptions
- Coverage is an estimate from the product label, not a guarantee.
- Two coats cover about half as much area as one coat at the same coverage rate.
- Texture, porosity, overspray, color changes, and touchups reduce usable coverage.
Example
Estimated one gallon of stain coverage coverage: 227 sq ft
How to use this calculator
- Enter paint volume in gal.
- Enter coverage per gallon in sq ft.
- Enter coats in count.
- Enter waste in %.
- Review the live estimate and compare it with the example result.
- Check the formula, assumptions, product labels, and site conditions before using the One Gallon of Stain Coverage Calculator result to plan materials.
Before you buy materials
- Round up to full gallons or containers and keep extra for touchups.
- Use the selected stain or sealer label as the final coverage source.
FAQ
How many square feet does 1 gallon of paint cover?
A common planning number is about 350 sq ft for one coat on a smooth surface, or about 175 sq ft for two coats.
How many square feet does 5 gallons of paint cover?
At 350 sq ft per gallon, 5 gallons covers about 1,750 sq ft for one coat or about 875 sq ft for two coats before waste.
Why does real paint coverage change?
Texture, porosity, primer, color change, application method, overspray, and touchups can all reduce real coverage.
How many sq ft for a 1 gallons at 250 sq ft per gallon, 1 coats, and 10% waste project?
A project using 1 gal paint volume, 250 sq ft coverage per gallon, 1 count coats, 10 % waste requires exactly 227 sq ft. This includes any waste percentages if applicable.
Related calculators
This calculator is for planning estimates only. Verify final quantities with product labels, project conditions, and a qualified professional when accuracy matters.