How this calculator works
Sealcoat is sold by the gallon, and the label gives how many square feet a gallon covers per coat. Multiply the area by the number of coats, add a little extra for waste, and divide by the coverage. Pails hold 5 gallons.
Worked example: a 50 × 12 ft driveway (600 ft²) with two coats at 80 ft² a gallon and 10% extra needs 16.5 gallons, which is 4 pails of 5 gallons. One coat needs 8.3 gallons.
Sealer for common driveways (two coats, 80 ft² a gallon, 10% extra)
Gallons and 5-gallon pails.
| Driveway | Area | Gallons | Pails |
|---|---|---|---|
| 20 × 10 ft | 200 ft² | 5.5 | 2 |
| 30 × 12 ft | 360 ft² | 9.9 | 2 |
| 50 × 12 ft | 600 ft² | 16.5 | 4 |
| 80 × 12 ft | 960 ft² | 26.4 | 6 |
| 100 × 16 ft | 1600 ft² | 44.0 | 9 |
Tips before you buy
- Clean the surface first: sweep, scrub oil stains with degreaser, and rinse. Sealer will not stick to dirt or oil.
- Fill cracks and holes before you seal, and let the filler cure.
- Apply in thin even coats with a squeegee or brush, and let the first coat dry before the second.
- Block the driveway for 24 to 48 hours, or as the label says.
- Re-seal every 2 to 3 years to protect the asphalt from sun, water and oil.
Tools & materials for this project
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Frequently asked questions
How much sealer do I need for a 50x12 driveway?
About 16.5 gallons for two coats at 80 ft² a gallon with 10% extra, or 4 five-gallon pails. One coat needs 8.3 gallons.
How many coats of driveway sealer should I apply?
Two thin coats are better than one thick coat, with the first allowed to dry before the second.
How many square feet does a 5 gallon pail cover?
It depends on the product and the surface, from about 250 to 500 ft² per coat, so check the label. At 80 ft² a gallon it is 400 ft² per coat.
How long should new asphalt wait before it is sealed?
Usually 6 to 12 months, so the oils have time to cure. Sealing too early can trap them.
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Estimates only. Results assume standard materials and simple shapes. Supplier products vary, and the final call on quantity, structure and safety is yours. Check your local code and your supplier's guidance before ordering.