Driveway Gravel Calculator
Calculate independent aggregate quantities for your compacted sub-base and wearing surface layers with compaction and pricing.
1Driveway Dimensions
2Layer 1: Sub-Base
Foundation3Layer 2: Surface Course
Top DressingReady to Calculate
Enter driveway size and both layers, then click Calculate Result.
Pouring 6 inches of loose pea gravel will cause cars to sink and spin out. An engineered driveway uses Crusher Run as a solid interlocked base, capped with 2 inches of angular #57 Stone for traction.
Standard Driveway Dimensions & Tonnage Reference
| Driveway Size | Area (sq ft) | Base (4" Crusher Run) | Surface (2" #57 Stone) | Total Tonnage Required |
|---|---|---|---|---|
| 10 × 20 ft (Single Short) | 200 sq ft | 3.6 tons | 1.8 tons | ~5.4 US Tons |
| 10 × 40 ft (Single Long) | 400 sq ft | 7.2 tons | 3.6 tons | ~10.8 US Tons |
| 20 × 20 ft (Double Short) | 400 sq ft | 7.2 tons | 3.6 tons | ~10.8 US Tons |
| 20 × 40 ft (Double Long) | 800 sq ft | 14.4 tons | 7.2 tons | ~21.6 US Tons |
Driveway FAQs
Q: How much gravel do I need for a 20x20 driveway?
A 20×20 ft driveway (400 sq ft) with a standard 6-inch total depth (4" Crusher Run base + 2" #57 stone surface) requires approximately 7.4 cubic yards (10.8 US tons) total. This breaks down into 4.9 yd³ (7.2 tons) of Crusher Run base and 2.5 yd³ (3.6 tons) of surface gravel.
Q: What is the best gravel for a driveway base and top coat?
The industry standard is a 2-layer system: Layer 1 (Sub-base) should be 4 to 6 inches of Crusher Run (also called dense grade, 21A, or road base), which contains stone dust that compacts rock-hard. Layer 2 (Surface) should be 2 to 3 inches of angular #57 crushed stone (3/4") or crushed limestone.
Q: Why shouldn't I use pea gravel for an entire driveway?
Pea gravel consists of rounded, smooth river pebbles with no angular edges or fine dust. Under vehicle tires, round pebbles act like ball bearings and shift continuously, creating deep ruts and making vehicles get stuck. Pea gravel should only be used as a light top dressing over a heavily compacted base if restrained by driveway stabilization grids.