Asphalt Sealer Calculator
Calculate gallons of driveway sealer needed for an asphalt surface.
Enter area and number of coats to get gallons, buckets to buy, and total cost.
Asphalt sealer is rated by coverage in square feet per gallon. The rate depends on the sealer type, the condition of the surface, and the number of coats.
Coverage rates (per gallon, per coat):
- Coal-tar sealer on smooth, well-maintained asphalt: 80 to 100 sq ft
- Coal-tar on weathered or cracked surfaces: 60 to 80 sq ft
- Acrylic / latex sealer (eco-friendly): 70 to 90 sq ft
- Driveway “fill and seal” with sand: 50 to 70 sq ft
The formula:
gallons = area_sqft x coats / coverage_per_gallon
Most manufacturers recommend two coats for a long-lasting result. The first coat soaks into the asphalt; the second creates the protective surface layer.
Sealer is sold in 5-gallon buckets almost universally. A typical home driveway is 600 to 800 sq ft. At 80 sq ft per gallon and two coats, that is:
700 x 2 / 80 = 17.5 gallons = 4 buckets (5 gal each, with leftover)
Practical tips:
- Clean and crack-fill before sealing. Sealer applied over loose debris peels off in months.
- Apply sealer when air and surface temps are 50 to 90 F (10 to 32 C). Below 50 F it does not cure; above 90 F it dries before you can spread it evenly.
- Avoid forecast rain for at least 24 hours after the second coat.
- Allow 24 to 48 hours between coats. Walk on it after 8 hours; drive after 24.
- Sealer weight: roughly 10 lbs per gallon. A 5-gallon bucket is 50 lbs — handle two-handed.
- Re-seal asphalt every 2 to 4 years. More often than that and you build up too thick a layer; less often and water gets in.
Cost: bulk coal-tar sealer runs around $25 to $40 per 5-gallon bucket. Premium acrylic sealers go $50 to $80. Add $15 to $30 for a squeegee applicator if you do not own one.