Deck Stain Calculator
How many gallons of deck stain do you actually need? This free deck stain calculator gives homeowners and pros an exact gallon estimate based on deck size, wood type, and surface condition — with separate totals for the deck surface, railings, and stair treads so nothing gets missed.
Most deck-stain shortages come from underestimating coverage. New cedar absorbs 30–40% more stain than previously sealed pine, and railings can soak up nearly a full gallon before you reach the stairs. Buy too little and your second coat dries unevenly between sections; buy too much and you waste $40+ per leftover gallon.
Adjusts automatically by wood porosity, includes 2-coat totals, and runs in under 30 seconds — no signup, no email.
Deck Stain Calculator
Calculate exact stain quantities based on industry research.
Deck Dimensions
Deck Railing
Stairs
Landings
Support Posts
Deck Underside + Structure
Wood & Stain Details
Want to Learn More?
Coverage rates for solid, semi-transparent, and clear stains with ASTM standards for wood preparation and application.
Read the Deck Stain Coverage GuideRelated Calculators
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How to Use This Calculator
- Enter deck dimensions: Input the deck area in square feet.
- Select wood type: Choose cedar, pressure-treated, or composite.
- Include railings & stairs: Enter linear feet if applicable.
- Review coverage: See gallons needed per coat based on wood porosity.
Deck Stain Coverage Rates
New wood absorbs more stain (150-200 sq ft/gal) than previously stained decks (250-300 sq ft/gal). Always apply 2 coats for proper protection.
Frequently Asked Questions
How much deck stain covers per gallon?
Solid stains cover 200-400 square feet per gallon. Semi-transparent stains have the widest range at 100-650 square feet per gallon depending on wood porosity. Clear sealers cover 250-350 square feet per gallon. Rough or weathered wood requires 20-50% more stain than smooth, new wood.
How many coats of deck stain should I apply?
Most deck stains require 2 coats for proper protection. Solid stains may achieve full coverage in 1-2 coats. Semi-transparent and clear sealers typically need 2 coats. Weathered or bare wood may require 3 coats for adequate penetration and protection.
What's the difference between deck stain and sealer?
Solid stains provide opaque color like paint but allow wood texture to show. Semi-transparent stains add color while showing wood grain. Clear sealers provide UV and moisture protection without changing wood color. All types penetrate wood rather than forming a surface film.
How often should I restain my deck?
Clear sealers need reapplication every 1-2 years. Semi-transparent stains last 2-3 years. Solid stains last 3-5 years. Factors affecting lifespan include sun exposure, foot traffic, climate, and wood type. Reapply when water no longer beads on the surface.