Inputs
Results
- Gross area
- 640.00 sq ft
- Excluded area
- 0.00 sq ft
- Net area
- 640.00 sq ft
- Waste / overlap factor
- 1.100
- Effective coverage
- 300.00 sq ft/gal
- Gallons required (exact)
- 4.693 gal
- Gallons to buy (rounded)
- 4.75 gal
- Suggested purchase mix
- 0 × 5-gal, 5 × 1-gal
- Plan cost (mix above)
- $125.00
- All 1-gal cost (rounded)
- $125.00
CSV exports your inputs and computed results. PDF captures the summary shown above.
Quick Presets
New asphalt, 2 coats, 10% waste
Weathered, 2 coats, 15% waste
Rough, 3 coats, 20% waste
Adjust coverage based on the product label. Older, porous surfaces need more material.
Example Data Table
| Scenario | L × W | Units | Coats | Waste % | Texture | Coverage | Gallons (approx) | |
|---|---|---|---|---|---|---|---|---|
| Single car, newer | 40 × 16 | ft | 2 | 10 | smooth | 300 | ||
| Two car, weathered | 60 × 20 | ft | 2 | 15 | moderate | 300 | ||
| Long lane, rough | 18 × 6 | m | 3 | 20 | rough | 250 |
Gallons are approximated using the same formula as the calculator with zero exclusions.
Formulas Used
- Gross area = Length × Width (convert m² → ft² using 1 m² = 10.7639 ft²).
- Net area = Gross area − Sum of excluded rectangles.
- Waste factor = 1 + Waste% ÷ 100.
- Effective coverage = Product coverage × Texture factor × Slope penalty.
- Gallons (exact) = Net area × Waste factor × Coats ÷ Effective coverage.
- Rounded gallons = Round up to nearest 0.25 gallon for practical purchasing.
- Container plan = Use 5-gal buckets first, then 1-gal cans.
How to Use This Calculator
- Enter driveway dimensions and select units.
- Choose coats, waste percentage, texture, and slope.
- Enter the product’s coverage rate from its label.
- Add any rectangular exclusions for gardens, drains, or aprons.
- Optionally add pricing to estimate total purchase cost.
- Press Calculate to update results and suggested container mix.
- Export your summary as CSV or PDF for ordering and records.
Typical Coverage by Surface Condition
| Surface | Approx. Range (sq ft/gal) |
|---|---|
| New / smooth asphalt | 325 – 400 |
| Weathered / hairline cracks | 275 – 325 |
| Rough / porous or patched | 200 – 275 |
Always prioritize the manufacturer’s printed coverage guidance for your specific sealant.
Coverage Impact of Coats & Waste
For a 600 sq ft driveway at 300 sq ft/gal:
- 1 coat, 5% waste ≈ 2.1 gal (round to 2.25).
- 2 coats, 10% waste ≈ 4.4 gal (round to 4.5).
- 2 coats, 20% waste ≈ 4.8 gal (round to 5.0).
Increasing coats and waste margin significantly raises required gallons and cost.
Driveway Size vs Gallons Needed
| Net Area (sq ft) | Setup | Gallons* |
|---|---|---|
| 400 | 2 coats, 10% waste | 3.0 |
| 600 | 2 coats, 10% waste | 4.5 |
| 800 | 2 coats, 10% waste | 6.0 |
| 1,000 | 2 coats, 15% waste | 7.5 |
*Assumes 300 sq ft/gal base coverage on moderately aged asphalt.