Asphalt Sealer Calculator

Find how many gallons of sealcoat a driveway needs, and the total material cost.

⏱ Updated: 18 Sep 2026

Calculator

Free asphalt sealer calculator: find how many gallons of sealcoat a driveway needs, and the total material cost.

Sealer Needed
gal
Estimated Cost
$
Surface Area
ft²
Total Area to Coat
ft²

Gallons are rounded up to the nearest whole can. 80 sq ft per gallon per coat is a commonly published rate for driveway sealer; older, more porous, or heavily cracked asphalt soaks up more and can drop coverage to 70 sq ft/gallon or less.

Enter your driveway's length, width, and coat count to calculate how many gallons of asphalt sealer you need.

How to Use the Asphalt Sealer Calculator

Enter the driveway's length and width, set how many coats you're applying, and adjust the coverage rate per gallon if your sealer's label lists a different figure. Price per gallon is optional.

Sealcoat is applied by the coat, not just by area, so this calculator multiplies area by the number of coats before dividing by coverage — a single coat and a double coat on the same driveway call for very different gallon totals.

The Formula

Area = Length × Width
Total area to coat = Area × Coats
Gallons needed = ⌈Total area to coat ÷ Coverage per gallon⌉

Surface Condition Changes Coverage More Than the Product Does

New, smooth asphalt tracks close to the 80 sq ft/gallon default. Older, cracked, or oxidized surfaces are more porous and drink up sealer faster — sometimes closer to 60–70 sq ft per gallon — so a driveway that hasn't been sealed in years will likely need more product than the default suggests.

Two Coats Is Common, Not Universal

Many sealer manufacturers recommend two coats for a fresh application and allow one for routine maintenance on a driveway already in good shape. Check your product's own instructions — the coat count field here is deliberately editable rather than fixed at two.

Weather Matters More Than It Does for Paint

Sealer needs a dry surface and a stretch of dry weather to cure properly, typically 24–48 hours per coat depending on temperature and humidity. None of that changes the material quantity this calculator returns, but it's worth planning around — sealer applied ahead of rain often has to be redone.