Deck Stain Calculator
Enter your surface area and product coverage rate to get a raw gallon requirement and a rounded-up purchase quantity.
Square feet per gallon, per coat.
Suggested purchase quantity
4 gal
- Total surface area
- 400 sq ft
- Raw requirement
- 4 gal
- Containers to buy
- 4
›Calculation details
Raw gallons = (deck + railing + stair area) × coats ÷ coverage per gallon. The purchase quantity then rounds that up to a whole number of your chosen container size.
How it works
Raw gallons = total surface area × number of coats ÷ your product's coverage rate. That's the exact amount the math needs — the purchase quantity then rounds up to a whole number of whatever container size you buy, since stores don't sell partial cans.
FAQ
Where do I find the coverage rate?
On the product label or can — it's usually given as square feet per gallon, and varies by wood type and how porous or weathered it is.
Should I include the railing and stairs?
If you're staining them in the same pass, yes — add their area in the optional fields so they're counted in the total.