How this calculator works
Asphalt sealer covers roughly 80 sq ft per gallon per coat. The calculator multiplies your driveway area by the number of coats and divides by that coverage.
480 sq ft ÷ 80 = 6 gallons.
Two thin coats beat one thick
Sealer lasts longer applied as two thin coats than one heavy one. Most driveways get a fresh seal every 2–3 years. Older, porous asphalt soaks up more than the label's coverage, so round gallons up to whole 5-gallon pails — that is the usual buy unit. Fill cracks and sweep the surface before sealing. If the pavement is failing rather than just faded, estimate a replacement with the asphalt calculator instead of resealing.
Frequently asked questions
How many gallons of sealer for a two-car driveway?
A typical 40×20 ft two-car pad is 800 sq ft. At 80 sq ft per gallon that is about 10 gallons for one coat or 20 gallons for two coats.
How many 5-gallon buckets do I need?
Divide the gallons by 5 and round up. Twenty gallons is four 5-gallon pails; 6 gallons is two pails.
How much does a gallon of driveway sealer cover?
About 80 sq ft per coat on older, porous asphalt; a bit more on smooth surfaces.
How often should I seal my driveway?
Every 2–3 years is typical, once the surface starts to fade or crack.
How much does it cost to seal a driveway?
Multiply the gallons or buckets needed by the product price, then add preparation, crack repair, delivery, or labor if applicable.
How many coats of driveway sealer should I apply?
Many asphalt sealers use two thin coats, but follow the product label for coverage, drying time, and application limits.