Example data table
Sample scenarios for planning and comparison.
| Path type | Size | Depth | Gravel | Order volume | Order weight |
|---|---|---|---|---|---|
| Rectangle | 30 ft × 4 ft | 3 in | Crushed Stone | 1.63 yd³ | ~2.00 US tons |
| Trapezoid | 25 ft, 3–5 ft wide | 3 in | Pea Gravel | 1.51 yd³ | ~1.77 US tons |
| Area override | 12.0 m² | 8 cm | Decomposed Granite | 1.11 m³ | ~1.61 tonnes |
Formula used
- Area is based on your shape or area override.
- Raw Volume = Area × Depth
- Order Volume = Raw Volume × Compaction × (1 + Waste%)
- Weight = Order Volume × Bulk Density
Compaction factor helps avoid under-ordering after settling. Waste covers spillage, leveling, and edge cleanup.
How to use this calculator
- Choose a unit system and calculation mode.
- Enter dimensions or an area override for irregular paths.
- Set depth, gravel type, compaction, and waste percent.
- Optional: add pricing and bag size for budgeting.
- Click Calculate Gravel and download CSV or PDF.
Planning depths for different walkway uses
For light garden foot traffic, a finished gravel depth of 5–7 cm (about 2–3 in) typically feels comfortable while staying easy to rake. For higher traffic, wheelbarrows, or sloped paths, plan 7–10 cm (about 3–4 in) to reduce rutting and exposed fabric. If your soil is soft or frequently wet, combine gravel with a compacted base layer rather than simply increasing depth.
Example: 30 ft × 4 ft at 3 in depth is 120 ft² with a practical finish height for most gardens.
Compaction and waste allowances that protect orders
Delivered aggregate settles after spreading and tampering. A common planning range is a compaction factor of 1.05–1.15 for rounded gravel and 1.10–1.20 for angular stone that interlocks. Waste covers spillage, edge shaping, and low spots; many projects land between 3–10% depending on borders and access.
- Small, straight paths: 1.08 compaction and 5% waste.
- Curved paths or tight access: 1.12 compaction and 8% waste.
- New edging and grade fixes: consider up to 10% waste.
Density differences by gravel type
The calculator converts volume to weight using bulk density. Typical values are 1450 kg/m³ for decomposed granite, 1520 kg/m³ for pea gravel, 1600 kg/m³ for crushed stone, and 1700 kg/m³ for river rock. Moisture content and fines can shift real deliveries by several percent, so “Custom Density” is useful when you have supplier data.
Heavier material affects transport limits and may change delivery fees even when volume is similar.
Delivery planning with volume and weight outputs
Many suppliers quote by cubic yard or by ton. For ordering checks, the tool reports both. A typical garden walkway order often falls near 1–3 yd³, which may be delivered in bulk or picked up in multiple loads. Weight estimates help avoid exceeding trailer limits and support scheduling when deliveries require smaller trucks.
| Scenario | Inputs | Order volume | Order weight |
|---|---|---|---|
| Front path | 30 ft × 4 ft, 3 in, 1.10, 5% | ~1.63 yd³ | ~2.00 US tons |
| Curved side path | Area 140 ft², 3 in, 1.12, 8% | ~2.05 yd³ | ~2.50 US tons |
| Courtyard strip | 12 m², 8 cm, 1.10, 5% | ~1.11 m³ | ~1.61 tonnes |
Budget forecasting using your supplier’s pricing
Pricing varies by region, rock type, and delivery distance. Enter a price per weight unit when quotes are “per ton” or “per tonne,” and choose price per volume when quotes are “per yard” or “per cubic meter.” If bagged product is used for small repairs, the bag estimate gives a quick purchasing count by rounding up.
For best accuracy, match the calculator unit system to the way your supplier bills the material.
FAQs
1) What depth should I use for a garden walkway?
Most walkways work well at 5–7 cm (2–3 in). Use 7–10 cm (3–4 in) for heavy traffic, slopes, or wheelbarrows. A compacted base usually improves performance more than extra top depth.
2) Why does the calculator include a compaction factor?
Gravel settles after spreading and tamping. Compaction factors (often 1.05–1.20) help you order enough material to reach the final depth once the stone locks together and voids reduce.
3) How do I choose the right gravel type?
Crushed stone interlocks and stays put, while pea gravel feels smooth underfoot but can shift. River rock drains well but is heavier. Choose based on stability, comfort, and how you expect the path to be used.
4) What if my walkway is irregular or curved?
Measure the area directly and use “Area override.” Break the walkway into rectangles, circles, or trapezoids, add areas together, and enter the total area for a reliable volume estimate.
5) Should I use waste percent even for small paths?
Yes. Waste accounts for edge shaping, spillage, and low spots. For simple straight paths, 3–5% is common. For curves, new edging, or uneven ground, 6–10% often avoids a second trip.
6) How accurate is the bag estimate?
Bag counts are volume-based and rounded up. Real results vary with bag labeling and settling. If you use supplier density or measured bag volume, accuracy improves for small patching or top-ups.
7) Do I need landscape fabric under gravel?
Fabric can reduce soil mixing and slow weed growth, but it may clog in silty areas. A well-compacted base and clean gravel improve durability. Consider local soil, drainage, and maintenance habits before installing fabric.