How much driveway sealer do I need?
Sealcoat is sold by the pail, so the goal is to turn your driveway's square footage into a whole number of pails. The formula this calculator uses is:
Pails = driveway area × coats ÷ coverage per pail, rounded up
Driveway area is simply length × width. We multiply by the number of coats (two is standard), divide by the area a single pail covers in one coat — about 400 sq ft on smooth asphalt — and round up, since you can't buy part of a pail. A handy rule of thumb: with two coats, plan on one 5-gallon pail per ~200 sq ft of driveway.
Sealer coverage by asphalt condition
Coverage is per 5-gallon pail, for a single coat. Rough, porous, or never-sealed asphalt drinks up the first coat, so it covers much less — lower the coverage value in the calculator to match.
| Asphalt condition | Coverage per pail (1 coat) |
|---|---|
| Smooth, previously sealed | 450–500 sq ft |
| Average, slightly weathered | 350–450 sq ft |
| Rough, porous, or first-time seal | 250–350 sq ft |
When and how to sealcoat
- Wait on new asphalt. Let a brand-new driveway cure 6–12 months before the first seal, or you'll trap the oils that need to evaporate.
- Reseal every 2–3 years. Not every year — over-sealing builds up a brittle layer that cracks and peels. Reseal when the surface turns gray and worn.
- Fill cracks first. Sealer is a coating, not a crack filler. Patch cracks and holes and let them set before you seal.
- Pick the right weather. Apply at 50–90°F on a dry day with no rain expected for 24 hours. Clean and dry pavement is essential.
- Two thin coats beat one thick one. Thin coats cure faster and last longer than a single heavy pass.
How to apply driveway sealer, step by step
- Clean thoroughly. Sweep, then pressure-wash or hose off dirt and scrub oil spots with a degreaser — sealer won't stick to a greasy or dusty surface.
- Fill cracks and holes. Use crack filler on anything wider than about ⅛ inch and patch potholes; let them cure per the label.
- Prime oil stains. Spot-prime stubborn oil spots with an oil-spot primer so the sealer can bond.
- Cut in the edges. Brush a band of sealer along the edges and around obstacles, where a brush reaches better than a squeegee.
- Squeegee on thin coats. Pour a bead and pull it across the asphalt with a squeegee/broom applicator in thin, even passes — thin is the key word.
- Wait, then second-coat. Let the first coat dry (usually a few hours), then apply the second at a right angle to the first. Keep traffic off for 24–48 hours.
DIY vs. hiring a pro
Sealcoating is one of the most DIY-friendly driveway jobs. Doing it yourself, the materials — a few pails of sealer, crack filler, and a squeegee applicator — typically run about $60–$150 for an average driveway. A professional sealcoat usually costs about $0.15–$0.25 per square foot, or roughly $100–$250 for a standard two-car driveway, and includes the cleaning and crack-filling labor. The DIY savings are real, but a pro is worth it for large, badly cracked, or steeply sloped drives.