Driveway Sealer Calculator
Enter your driveway size to get the sealer you need in gallons, plus an estimated cost.
Sealer needed
Estimated cost
How to calculate driveway sealer
Sealer is sold by the gallon. Find the driveway area, multiply by the number of coats, then divide by the coverage per gallon and round up.
Formula: gallons = driveway area (sq ft) × coats ÷ coverage per gallon, rounded up
Worked example: 20 ft × 20 ft driveway, 2 coats
Driveway area = 20 × 20 = 400 sq ft. With 2 coats: 800 sq ft. At 100 sq ft per gallon: 800 ÷ 100 = 8 gallons.
Two thin coats
Two thin coats last longer than one thick coat, which can peel. Let the first coat dry fully before the second.
Common driveway sizes
Cost tips
Prices on this page are editable estimates, not quotes. Get 2 to 3 local quotes before you buy, and ask if delivery is included. Delivery, tax and waste can change the total a lot. Order a little extra for cuts and breakage, and confirm final quantities with your supplier or a qualified professional.
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Frequently asked questions
How much sealer do I need for a 20x20 driveway?
A 20 ft by 20 ft driveway needs 8 gallons for 2 coats at 100 sq ft per gallon.
How many coats of sealer?
Two thin coats last longer than one thick coat. Let the first coat dry before the second.
How much area does a gallon cover?
About 100 sq ft per coat on asphalt. Rough or old asphalt uses more.
How often should I seal?
Every 2 to 3 years for driveways, or when water stops beading on the surface.
Are the prices accurate?
Prices are editable estimates. The defaults are typical US figures, and your local price can be higher or lower.