Concrete Sealer Calculator
Estimate concrete sealer for a driveway, patio or garage floor in gallons. Coverage runs about 250 sq ft per gallon per coat; two coats is typical.
Concrete Sealer calculator
How it's calculated: Length ft × width ft = square feet; multiply by coats (2 is typical) and divide by about 250 sq ft per gallon, rounding up.
How to estimate concrete sealer
- Coverage varies a lot by product and surface porosity - check the label and round up.
- Two thin coats outperform one thick coat. Let the first cure per the label before the second.
- Seal only fully cured concrete (usually 28+ days) and a clean, dry surface.
- Match the sealer to the job: film-forming acrylics add sheen and need recoating more often, while penetrating silane/siloxane sealers protect without changing the look.
- Test a small, out-of-the-way patch first - some sealers darken concrete or add gloss you may not want everywhere.
Frequently asked questions
How many square feet does a gallon of concrete sealer cover?
Roughly 200-300 sq ft per coat for many sealers, but porous or broom-finished concrete uses more.
How long does concrete sealer last?
Film-forming acrylics typically need recoating every 1-3 years; penetrating sealers often go 5-10. Traffic, sun and deicing salts shorten either.
How long before I can use the sealed surface?
Foot traffic is usually fine within hours to overnight; keep vehicles off for roughly 24-72 hours. Cure times vary a lot by product, so the label wins.
Do I really need to seal concrete?
It is optional on a sheltered patio, but worth it for driveways in freeze-thaw climates, anywhere deicing salt lands, and surfaces prone to oil or rust stains. Sealing is cheap insurance against surface spalling.
How do I know when to reseal?
Watch how water behaves. When rain stops beading and the surface absorbs water and darkens evenly, the sealer has worn through and it is time for another coat.