Part of the DIY & Home collection — 4 tools available
Stain Calculator — Wood Stain Coverage
Calculate how much wood stain you need based on surface area and number of coats. Estimate cans of stain needed for decks, fences, and furniture.
About This Calculator
Applying stain to wood surfaces protects against moisture penetration, UV damage, and everyday wear — but buying too little means an uneven finish with visible lap marks, and too much wastes money on product you can't return. Coverage varies significantly by stain type and wood condition: oil-based stains cover 150-300 square feet per gallon on smooth surfaces, while rough-sawn or weathered wood absorbs 30-50% more product. Two coats double the requirement. Our stain calculator accounts for surface texture, number of coats, and product-specific coverage rates to help you order the right amount.
The Formula Behind This Calculator
Area = Length * Width (or Height) Gallons = Area / Coverage rate 2 coats recommended for protection
Understanding the math helps you verify results and make better decisions for your project.
How to Use
- 1Measure the length and width (or height) of the surface to stain.
- 2Set how many sides of the wood need staining.
- 3Choose the number of coats (2 is standard for most projects).
When to Use
- →Staining a deck, fence, or exterior wood structure.
- →Finishing interior woodwork, furniture, or cabinets.
- →Estimating stain quantities for a large woodworking project.
Tips
- ✓Rough or weathered wood absorbs 50-100% more stain than smooth new wood.
- ✓Always test stain on a hidden area first — wood species dramatically affect color.
- ✓Apply stain in the direction of the wood grain and maintain a wet edge to avoid lap marks.
FAQ
How much area does one gallon of stain cover?
Smooth wood: 200-300 sq ft per gallon. Rough/sanded wood: 150-200 sq ft. Weathered or pressure-treated wood: 100-150 sq ft. Check the product label for specific coverage.
How many coats of stain should I apply?
Two coats is standard for most exterior projects. A single coat may work for semi-transparent stains on smooth new wood. Three coats is recommended for solid color stains on weathered surfaces.
Should I sand before staining?
Yes. Sand to 120-grit for smooth woods or 80-grit for rougher surfaces. Sanding opens the wood grain so stain absorbs evenly. Always sand with the grain.
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