Asphalt Calculator Blog · Sealcoating

How Much Sealer Do I Need? Driveway Coverage Calculator

The simple rule is 80 square feet per gallon for one coat on a typical surface. Smoother surfaces stretch the coverage. Rougher ones cut it. Here is the full math with a coverage calculator below.

You measured the driveway, you walked into the home improvement store, and you stared at a wall of 5 gallon pails. How many do you actually need? The honest answer is most people overspend by one pail or run short by half a pail. Both are easy to avoid with the right math. Cross-check sizing on the sealer calculator tool when you are done here.

How Much Sealer Do I Need? Driveway Coverage Calculator
A typical 18 by 20 ft single-car driveway uses 4 to 5 gallons of sealer at one coat. Two coats roughly doubles that.

The 80 square feet per gallon baseline

Almost every homeowner driveway sealer on the shelf covers about 80 square feet per gallon on one coat. A 5 gallon pail covers about 400 square feet at one coat. Two coats halves the coverage. So one pail does 200 square feet of a proper two-coat job. That is the entire rule before any adjustments. Manufacturers print this on the pail in small text. The number lines up across brands because the chemistry is similar. For brand differences see best sealer brands 2026 and sealer types compared.

Coverage calculator

Enter your driveway dimensions and pick a surface condition. The calculator returns square footage, gallons needed, pails to buy, and an estimated cost.

Sealer coverage

Inputs default to a typical 18 by 20 ft driveway with two coats on a typical surface.

360square feet
9gallons needed
25-gal pails to buy
$70estimated cost
A typical 18 by 20 ft driveway needs 9 gallons of sealer for two coats. Buy 2 pails.

How surface condition changes coverage

The 80 sq ft per gallon number assumes a typical surface. Conditions change the math. Smoother surfaces stretch to 100 sq ft per gallon because the sealer sits on top. Rougher surfaces with raveling drop to 65 sq ft per gallon because the sealer soaks in. A 1 year old driveway is smooth. A 10 year old unsealed driveway is rough. Most driveways in the middle are typical. See what sealcoating actually does for why a porous surface drinks more sealer.

One coat or two

Two coats is the standard for a full sealcoat job. The first coat soaks into the pores and bonds with the asphalt. The second coat forms the wear surface that takes UV, water, and tires. A single coat works for a refresh on a driveway sealed within the last 3 years. The first coat is mostly still there, so the new coat just rebuilds the wear layer. Apply the second coat perpendicular to the first to even out lap marks. See the full sealcoat tutorial for application.

The 10 percent waste buffer

Buy 10 percent more than the math says. You will use some on the edges and brush work, some on touch-ups, and some on the last few square feet that always need a second pass. A 5 gallon pail is also hard to scrape clean. The buffer keeps you from running back to the store with a sticky squeegee. Leftover unopened pails store fine for a year if kept indoors above freezing.

How to measure an irregular driveway

Most driveways are not perfect rectangles. Use this method.

  • Rectangle the area. Use the longest length and the widest width.
  • Ignore lost corners under 10 percent of total area. A small angled cut at the street is too small to matter.
  • For an L shape, measure each leg as its own rectangle and add them.
  • For an apron at the garage, add a small rectangle for the flare.
  • For a circle or curve, measure the bounding rectangle and subtract 25 percent.

The main asphalt calculator handles irregular shapes piece by piece if you want to be exact.

Common driveway sizes

Use these as a sanity check against your own measurement before buying pails.

  • 1-car single-bay: 12 ft by 20 ft = 240 sq ft. 1 pail for 2 coats.
  • Standard 2-car: 18 ft by 20 ft = 360 sq ft. 2 pails for 2 coats.
  • Wide 2-car with apron: 20 ft by 30 ft = 600 sq ft. 3 pails for 2 coats.
  • 3-car: 30 ft by 30 ft = 900 sq ft. 5 pails for 2 coats.
  • Long suburban: 14 ft by 60 ft = 840 sq ft. 5 pails for 2 coats.
  • Rural long driveway: 12 ft by 200 ft = 2400 sq ft. 12 pails for 2 coats.

Where to buy driveway sealer in 2026

The big box stores carry the homeowner brands. Home Depot stocks Latex-ite, Henry, and Black Jack. Lowes carries Latex-ite and Sakrete. Tractor Supply carries Black Jack and a few private label brands. Menards carries Quikrete and Tamko. Ace Hardware stocks a smaller selection. Premium acrylic sealers are more often found at paint stores like Sherwin-Williams. Contractor supply houses like SealMaster sell commercial grade sealer in bulk. Expect 30 to 45 dollars per 5 gallon pail in 2026 for homeowner sealer. Premium acrylic runs 50 to 80 dollars. The 2026 sealcoating cost guide covers DIY vs pro pricing.

Don't forget crack filler and oil primer

Sealer is one line item. Two others almost always go with it. Crack filler for any hairline crack wider than 1/8 inch. See crack repair. Oil spot primer for any visible drip or spill. See oil stain removal. Both go on before the sealer and add about 30 to 60 dollars to a typical job. Skipping either is one of the most common DIY traps. See DIY sealcoating mistakes.

Bottom line

Plan on 80 sq ft per gallon at one coat for a typical driveway. Two coats halves that. A standard 18 by 20 ft single-car driveway needs 9 gallons or 2 pails for a full two-coat job. A 2-car driveway around 600 sq ft needs 15 gallons or 3 pails. Add 10 percent for waste. Surface condition shifts the number up or down by about 20 percent. For application steps see how to sealcoat DIY and check whether DIY math beats hiring out at is sealcoating worth it.

For brand-side technical sheets, the National Asphalt Pavement Association publishes sealer guidance, and the Asphalt Institute has notes on emulsion chemistry and coverage rates.

FAQ

Sealer Coverage FAQ

How much sealer do I need for my driveway?

Use 80 sq ft per gallon at one coat as the baseline. A standard 18 by 20 ft driveway needs about 4.5 gallons for one coat or 9 gallons for two.

How many gallons for a 1000 sq ft driveway?

About 12.5 gallons for one coat or 25 gallons for two. Buy 3 pails for one coat or 5 pails for two, plus a 10 percent buffer.

One coat or two coats of driveway sealer?

Two on a new or cleaned driveway. One for a refresh within 3 years of the last seal. Apply the second perpendicular to the first.

How much area does a 5 gallon pail cover?

About 400 sq ft at one coat or 200 sq ft at two coats on a typical surface. Plan pails accordingly.

Does surface condition change coverage?

Yes. Smooth surfaces stretch to 100 sq ft per gallon. Rough surfaces drop to 65 sq ft per gallon. Typical is 80.

Where can I buy driveway sealer in 2026?

Home Depot, Lowes, Tractor Supply, Menards, Ace, and contractor supply houses like SealMaster. Expect 30 to 45 dollars per pail for homeowner sealer.

Related reading

Keep Going