Deck Stain Calculator

ft
ft
sq ft/gal
Check product label. Typical: 150–250 sq ft/gal for solid stain.
Construction

Calculate how many gallons of deck stain are needed based on deck area and product coverage.

Formula

Gallons = (area ÷ coverage) × number of coats
  • New, porous wood absorbs more stain — may need additional coat.
  • Allow first coat to dry fully before applying second coat.

20×12 ft deck, 200 sq ft/gal, 2 coats

Inputs
  • Deck Length: 20 ft
  • Deck Width: 12 ft
  • Stain Coverage: 200 sq ft/gal
  • Number of Coats: 2

240 sq ft ÷ 200 × 2 = 2.4 gallons → round up to 3 gallons.

Frequently asked questions

How often should I restain a deck?
Every 2–3 years for semi-transparent stain; 3–5 years for solid stain.