Calculator
Formula used
Compacted Volume = Area × Depth
Volume_ordered = Volume_with_waste × (1 + Compaction%/100)
Tons (US) = Weight(lb) ÷ 2000
Tonnes = Weight(kg) ÷ 1000
Subtotal = Material Cost + Delivery Fee
Tax = Subtotal × Tax%/100
Total = Subtotal + Tax
How to use this calculator
- Choose your unit system, then enter walkway length and width.
- Enter the compacted base depth; 3–6 inches is common.
- Select a gravel type, or choose custom density if known.
- Add waste and compaction allowances to match your conditions.
- Select your supplier pricing method and enter unit price.
- Include delivery and tax to estimate your complete total.
- Click Calculate, then export results to CSV or PDF.
Example data table
| Length | Width | Depth | Waste | Compaction | Ordered Volume | Estimated Weight |
|---|---|---|---|---|---|---|
| 30 ft | 4 ft | 4 in | 7% | 10% | ~2.17 yd³ | ~2.56 tons |
| 15 ft | 3 ft | 3 in | 5% | 8% | ~0.53 yd³ | ~0.63 tons |
| 10 m | 1.2 m | 10 cm | 7% | 10% | ~1.41 m³ | ~2.26 tonnes |
1) Why a gravel base matters
A gravel base distributes loads, keeps pavers or stepping stones stable, and limits frost heave and rutting. For garden walkways, a well-graded crushed aggregate base helps water move laterally while maintaining strength. A thin, uneven base often leads to settling, rocking stones, and low spots after heavy rain.
2) Typical base depths for walkways
Light foot-traffic paths commonly use 3–4 inches (7.5–10 cm) of compacted base on firm soil. Softer soils, slopes, or occasional wheelbarrow traffic can benefit from 5–6 inches (12.5–15 cm). This calculator uses your compacted depth and adds allowances so the delivered amount better matches what you install.
3) Waste and compaction allowances
Waste covers trimming edges, small grade corrections, spillage, and rounding to supplier quantities. A 5–10% waste factor is common for straight runs; complex curves can be higher. Compaction allowance accounts for void reduction when you plate-compact. Depending on moisture and gradation, ordering 8–12% extra often prevents shortfalls.
4) Density, tons, and volume conversions
Suppliers may price by ton/tonne, cubic yard, cubic meter, or bag. Typical landscape aggregate densities fall roughly in the 95–105 lb/ft³ range (about 1,520–1,680 kg/m³). The calculator converts your ordered volume into weight using density, then provides both cubic and tonnage outputs for easier quoting.
5) Choosing a gravel type
For bases, “crushed” or “well-graded” stone compacts tightly and resists shifting. Pea gravel is rounder, drains well, but tends to move underfoot and is better as a top layer rather than a base. If you have a local spec (for example, road base), use custom density for improved estimates.
6) Cost drivers you can control
Material price is only part of the total. Delivery fees, minimum loads, and taxes can change your final number significantly. Reduce waste by staking your layout, maintaining consistent width, and setting edge restraints early. If you must hand-carry material, consider bag pricing and staged deliveries for efficiency.
7) Installation checkpoints for durability
Excavate to the planned depth plus your surface layer thickness, then remove organic soil. Use geotextile on soft subgrade to limit mixing. Place base in lifts of 2–3 inches (5–7.5 cm), compact each lift, and verify slope (about 1–2% away from structures) for drainage.
8) Using results to order confidently
Start with the “Ordered volume” value, then compare it to how your supplier sells material. If pricing is by ton, use the tonnage output; if by yard or meter, use the matching volume output. Add a small buffer when availability is limited, because partial deliveries often cost more overall.
1) What base depth is best for a simple garden path?
On firm soil with foot traffic, 3–4 inches (7.5–10 cm) compacted is common. Increase depth for soft soil, heavy rainfall, or wheelbarrow use. Always maintain drainage slope to avoid puddling.
2) Should I use crushed stone or pea gravel for the base?
Crushed, well-graded stone compacts and locks together, making it ideal for bases. Pea gravel is rounded and tends to shift; it’s better for decorative top layers or areas where movement is acceptable.
3) How much waste should I add?
Many straight walkways use 5–10% waste. Add more for curves, irregular edges, or uncertain grades. If you’re ordering by the truckload, rounding up can reduce the risk of running short.
4) Why does compaction change how much gravel I need?
Compaction reduces air voids, so loose material settles to a smaller final thickness. Ordering an extra 8–12% is common for compactable base stone. The allowance helps your delivered amount match the compacted design depth.
5) My supplier quotes cubic yards, but I want tons. What do I do?
Use the calculator’s density-based conversion. Enter a gravel type or custom density, then compare “Ordered volume (yd³)” and “Estimated weight (tons).” If your quarry provides a tested density, use that for best accuracy.
6) Do I need landscape fabric under the base?
Fabric helps on soft or silty soils by separating base from subgrade and reducing contamination. It’s less critical on firm, well-draining soils, but still useful where roots, mud, or seasonal saturation could mix into the base.
7) Can I price the project using bagged gravel?
Yes. Select “Per bag,” enter bag price and bag weight. Bagged material costs more per unit but is convenient for small projects or tight access. The calculator also estimates the number of bags needed, rounded up.