Gravel & Crushed Stone Calculator
Measure your path, patio base or driveway, choose the depth and material, and see how many cubic yards, tons or bags of gravel to order, plus the cost.
How to use the Gravel & Crushed Stone Calculator
- Pick Imperial or Metric to choose how the main result is shown.
- Enter each area: choose a shape and unit, then type the dimensions. Use + Add area for extra beds or sections.
- Set the depth with a preset or your own value, and the extra percentage for compaction and waste.
- Choose the material so the weight uses a typical density, or enter your supplier's density.
- Add a price per ton, cubic yard or bag to see the cost, then press Calculate or Copy result.
Gravel calculation formula
Gravel is ordered by volume (cubic yards or cubic meters) or by weight (tons or tonnes). The calculator works it out in three steps:
- Volume = area × depth. With feet: length (ft) × width (ft) × depth (in) ÷ 12 = cubic feet. Divide by 27 for cubic yards, or multiply by 0.0283 for cubic meters.
- Extra: multiply by 1.10 for 10% compaction and waste (more for road base).
- Weight = volume × density. With cubic yards and tons per cubic yard: yd³ × 1.4 = tons.
Example: a 10 × 20 ft patio base 3 inches deep is 10 × 20 × 3 ÷ 12 = 50 ft³. With 10% extra that is 55 ft³ = 2.04 yd³. In pea gravel at about 103.7 lb/ft³ it weighs 5,704 lb, or 2.85 US tons (2.59 tonnes), or 110 bags of 0.5 ft³.
For a circle use π × diameter² ÷ 4 for the area, and for a triangle use base × height ÷ 2. Split L-shaped or curved areas into simple shapes and add them as separate areas.
Typical gravel densities
These are typical loose (as-delivered) values used by the presets. Moisture, stone type and grading change them, so ask your supplier for their figure if you are ordering by weight.
| Material | lb/ft³ | US tons/yd³ | t/m³ |
|---|---|---|---|
| Pea gravel | ≈ 104 | ≈ 1.40 | ≈ 1.66 |
| Crushed stone #57 (3/4") | ≈ 100 | ≈ 1.35 | ≈ 1.60 |
| River rock | ≈ 100 | ≈ 1.35 | ≈ 1.60 |
| Crusher run / road base | ≈ 111 | ≈ 1.50 | ≈ 1.78 |
| Decomposed granite | ≈ 96 | ≈ 1.30 | ≈ 1.54 |
| Dry sand | ≈ 100 | ≈ 1.35 | ≈ 1.60 |
| Lava rock | ≈ 37 | ≈ 0.50 | ≈ 0.59 |
Gravel coverage per cubic yard
One cubic yard (27 ft³) of gravel covers this area at common depths. In metric, one cubic meter covers 20 m² at 5 cm, 13.3 m² at 7.5 cm and 10 m² at 10 cm.
| Depth | Coverage of 1 yd³ | Typical use |
|---|---|---|
| 2 in | 162 ft² | Top dressing, decorative paths |
| 3 in | 108 ft² | Garden paths, beds, play areas |
| 4 in | 81 ft² | Patio or shed base, light driveways |
| 6 in | 54 ft² | Driveway base, drainage trenches |
| 8 in | 40.5 ft² | Heavy-use driveway base on soft ground |
Choosing the right gravel
- Driveways: a compacted base of crusher run or #3/#4 stone, topped with 2–3 inches of #57 or similar angular stone that locks together. Rounded pea gravel rolls under tires.
- Drainage and French drains: clean, washed #57 stone lets water through; avoid crusher run, whose fines clog.
- Paths and patios: decomposed granite or crushed fines compact to a firm surface; pea gravel is comfortable underfoot but shifts.
- Under pavers: about 4 inches of compacted base plus 1 inch of bedding sand.
Laying landscape fabric under decorative gravel slows weeds and stops the stone sinking into the soil, which means less top-up over time.
Frequently asked questions
How much does a cubic yard of gravel weigh?
Most gravel and crushed stone weighs about 1.3 to 1.5 US tons per cubic yard (roughly 2,600 to 3,000 lb), or about 1.5 to 1.8 tonnes per cubic meter. Light materials such as lava rock weigh much less, and wet material weighs more.
How many tons of gravel do I need for a driveway?
Multiply length × width × depth in feet to get cubic feet, divide by 27 for cubic yards, then multiply by about 1.4 tons per cubic yard. A 12 × 50 ft driveway with 4 inches of gravel is 200 ft³ or 7.4 yd³, which is about 10.4 tons before adding extra for compaction.
How deep should gravel be?
Decorative paths and beds usually need 2 to 3 inches (5–7.5 cm). A patio or shed base is often 4 inches of compacted base, and a driveway typically needs 4 to 8 inches of base stone plus 2 to 3 inches of top gravel, more on soft soil.
Why add extra for compaction?
Crushed stone and especially crusher run settle when they are compacted or driven on, so you need more loose material than the finished volume. Adding 10% covers spillage and uneven ground; 15–25% is common for compacted road base.
How many bags of gravel make a ton?
A typical 0.5 cubic foot bag of gravel weighs about 45 to 50 lb, so a US ton (2,000 lb) is roughly 40 to 45 bags. For more than about a cubic yard, buying in bulk is usually much cheaper than bags.
What is the difference between a ton and a tonne?
A US (short) ton is 2,000 lb (907 kg). A metric tonne is 1,000 kg (2,204.6 lb). Suppliers in the US usually price by the short ton; most other countries use tonnes.