Asphalt Calculator
Calculate the exact amount of asphalt needed for your paving project, including volume, weight, and cost estimation.
Enter dimensions and click calculate to see results.
How It Works
How This Calculator Works
This calculator determines asphalt volume by multiplying length × width × depth for rectangular areas, or πr² × depth for circular slabs. The calculator converts all units to a standard measure before calculating and includes options for adding a waste factor and calculating costs.
The Formula
For rectangular areas:
Volume = Length × Width × Depth
For circular areas:
Volume = π × (Diameter/2)² × Depth
With waste factor:
Adjusted Volume = Volume × (1 + Waste%/100)
Weight calculation:
Weight = Volume × Density
Cost calculation:
Cost = Volume × Price per unit volume
Important Considerations
- Always add a 5-15% waste factor for spillage and compaction
- Standard asphalt density is approximately 145 lbs/ft³ (2,322 kg/m³)
- For road construction, consult local transportation department specifications
- Asphalt typically requires 24-48 hours to fully cool and set before heavy use
Frequently Asked Questions
What's the difference between asphalt and concrete?
Asphalt is a mixture of aggregates and bitumen (a petroleum product), while concrete is made from cement, water, sand, and gravel. Asphalt is generally more flexible, faster to install, and often less expensive than concrete.
How thick should my asphalt driveway be?
Residential driveways typically need 2-3 inches of asphalt over a 6-8 inch gravel base. Commercial driveways or areas with heavy traffic may require 3-4 inches of asphalt over a 8-10 inch base.
How long does asphalt take to cure?
Asphalt typically sets enough for light foot traffic within a few hours, but it generally needs 24-48 hours before it can handle vehicle traffic. Complete curing and hardening can take up to 6-12 months depending on climate.
What if my asphalt area has an irregular shape?
For irregular shapes, divide the area into simpler geometric shapes (rectangles, circles), calculate the volume for each part separately, and then add them together for the total volume.