🎨Deck Stain Calculator
Find out how many gallons of stain your deck and railings need.
Your deck
You'll need about
2.8 gallons
352 sq ft to cover · buy 3 cans
cans
3
sq ft
352
coverage per gallon
250 sq ft
🛒 Shopping list
- Deck stain (1 gallon cans)3 cans
- Deck cleaner (1 gallon)1 jugs
Old, dry wood soaks up stain fast. Do a small test patch first and keep one extra can on hand.
How it works
Gallons = (deck area + railing length × 4 sq ft) × coats ÷ coverage. Coverage starts at 250 sq ft per gallon for new, smooth wood. Weathered wood soaks up about 20% more (200 sq ft), and rough-sawn wood about 40% more (150 sq ft).
Worked example
A 192 sq ft deck with 40 ft of railing, 2 coats, new wood:
- 40 ft × 4 = 160 sq ft of railing
- (192 + 160) × 2 = 704 sq ft
- 704 ÷ 250 = 2.8 gallons → buy 3 cans
Questions people ask
About 250 sq ft on new, smooth wood, and closer to 150–200 sq ft on old or rough wood.
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Last updated September 28, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.