Gravel Calculator
Gravel Results
| Depth | 1 Ton Covers | 1 Yd³ Covers | Best Use |
|---|---|---|---|
| 2 inches | ~100 sq ft | ~162 sq ft | Top dressing, decorative beds |
| 3 inches | ~65 sq ft | ~108 sq ft | Paths, playgrounds |
| 4 inches | ~50 sq ft | ~81 sq ft | Driveways, base layers |
| 6 inches | ~33 sq ft | ~54 sq ft | Heavy traffic, drainage |
A properly built gravel driveway uses three compacted layers:
Quarries and landscape suppliers sell gravel by the ton. Concrete suppliers sell by the cubic yard. Our calculator outputs both so you can order correctly regardless of how your supplier quotes. The conversion depends on material density — crushed stone is 1.4 tons per cubic yard, while lighter materials like decomposed granite run about 1.25 tons per yard. When in doubt, add 10–15% to your calculated amount to account for compaction loss and waste during delivery and spreading.
Gravel Base Depth by Project Type
| Project | Base Depth | Stone Size | Notes |
|---|---|---|---|
| Concrete patio | 4" | Crushed #57 or roadbase | Compact in 2" lifts |
| Concrete sidewalk | 3–4" | Crushed #57 | More if soil is poor |
| Concrete driveway | 4–6" | Roadbase / Class 5 | 6" in clay or freeze zones |
| Garage slab | 4" | Crushed #57 | Vapor barrier on top |
| Asphalt driveway | 6–8" | Roadbase / Class 5 | Heavier than concrete base |
| Paver patio | 4–6" | Roadbase + 1" sand | Edge restraint required |
| Shed foundation | 4" | Crushed #57 | Level + compact |
| Gravel driveway (only) | 8–12" | 3 layers: roadbase → #57 → topcoat | Each layer compacted |
Why a Gravel Base Matters
A properly compacted gravel base does five jobs at once: it spreads load evenly to prevent cracking, drains water away from the slab, prevents frost heave in cold climates, levels the surface for accurate slab thickness, and gives the concrete a firm working surface during the pour.
The single biggest reason DIY concrete projects fail is inadequate base preparation. A 4-inch concrete slab on bare dirt will crack within 2–3 freeze-thaw cycles. The same slab on 4 inches of compacted roadbase will last 30+ years.
Compaction matters as much as quantity. Loose gravel offers almost no support. Aim for at least 95% compaction, achieved by spreading in 2-inch lifts and going over each lift with a plate compactor 3–4 passes minimum.
Roadbase vs Crushed Stone vs Pea Gravel
Mixed sizes from dust to 1". Compacts hard. Best for: driveways, heavy load applications, paver bases.
¾" angular stones, no fines. Drains well. Best for: patios, sidewalks, garage slabs in dry-soil regions.
Smooth round ¼–½" stones. Won't compact. Best for: drainage layers under footings — NOT base for slabs.