Driveway · updated 2026
Driveway Sealcoat Calculator
Sealcoating is the cheapest life-extension an asphalt driveway can get — but the coverage math trips people up because it depends on coats and the driveway’s condition. This driveway sealcoat calculator takes your driveway’s length and width, applies real coverage rates (about 100 sq ft per gallon per coat on average asphalt), and returns exact gallons plus how many 5-gallon buckets to buy, with 2026 DIY and pro costs. Older, rougher asphalt drinks more; drop the coverage rate if yours is badly weathered.
100 is typical; use 80 for rough, weathered asphalt
Show the math
Area = 40 × 20 = 800.0 sq ft
Gallons = 800.0 × 2 coat(s) ÷ 100.0 sq ft/gal = 16 gal
Buckets = 16 ÷ 5 = 4 (rounded up)
DIY cost = 4 buckets × $25–$35/bucket
Pro cost reference = 800.0 sq ft × $0.15–$0.25/sq ft
What the numbers mean
The calculator converts your measurements into a practical purchase quantity using a documented coverage or spacing assumption.
Any whole-unit quantity is rounded up so the result does not leave you short during the project.
Use the cost range as a planning baseline and confirm the final quantity, availability, and delivery charge with your local supplier.
2026 material prices
| Material | 2026 average price | Note |
|---|---|---|
| Asphalt sealer, 5-gal bucket | $25.00 – $35.00 / 5-gal bucket | Retail; covers ~500 sq ft per coat |
| Pro sealcoating service | $0.15 – $0.25 / sq ft | Includes crack filling at most companies |
Material and service rates: Phase 2 2026 national-average guide, Sep 2026. Local prices vary. 2026 U.S. national averages. Prices vary by region and retailer — confirm locally before buying.
Pro tips
- Apply two thin coats, not one thick one — thick coats crack and peel within a year.
- Fill cracks first and let the filler cure 24 hours; sealer over open cracks is wasted money.
- Apply when air and surface temps are above 50°F with no rain for 24–48 hours — summer mornings are ideal.
- Keep cars off 24–48 hours; foot traffic is fine after 4–6 hours.
- An 800 sq ft driveway needs 16 gallons (4 buckets) for two coats — a single Saturday morning job.
- Edge with a brush and roll the field; a squeegee works the sealer into the aggregate better on rough asphalt.
Common questions
Frequently asked questions
How much sealcoat for an 800 sq ft driveway?
16 gallons for two coats at 100 sq ft/gal — that is 4 five-gallon buckets.
How many square feet does a gallon of sealer cover?
About 80–120 sq ft per gallon per coat; use 80 for rough, weathered asphalt.
How many coats of sealcoat?
Two thin coats. One thick coat looks done faster but cracks and peels early.
How often should I sealcoat?
Every 3–5 years, or when the surface turns light gray and starts shedding aggregate.
When is the best time to sealcoat?
Summer, when temps stay above 50°F day and night with 24–48 hours of dry weather after application.
DIY vs pro sealcoating cost?
DIY runs about $100–$140 in materials for an 800 sq ft driveway; a pro charges roughly $120–$200 including crack filling.
Related calculators
Planning estimates only. Prices are 2026 U.S. national averages and vary by region — confirm with your local supplier before buying.