How to calculate how much gravel you need
- Measure the area you want to cover — length and width for rectangles, or the diameter for a round bed or fire-pit area.
- Choose the depth in inches. Depth has the biggest effect on the order, so check what your project needs (see below).
- Pick the material. Each stone type has a different weight per cubic yard, which matters because most quarries and landscape yards sell by the ton.
- Add an allowance of about 10% for compaction and uneven ground.
Gravel formula: cubic yards and tons
Tons = Cubic yards × Density (tons per cubic yard)
Worked example: a gravel path
A path 40 ft long, 10 ft wide and 4 in deep holds 40 × 10 × 4 ÷ 12 = 133.33 cubic feet, or 4.94 cubic yards. Pea gravel weighs about 1.4 tons per cubic yard, so that is 6.91 tons before any waste allowance.
Gravel weight by type
Typical bulk densities used by this calculator. Wet material and finer stone weigh more, so treat these as planning figures:
| Material | Tons per cubic yard | Pounds per cubic yard |
|---|---|---|
| Pea gravel | 1.4 | 2,800 |
| Crushed stone #57 | 1.42 | 2,840 |
| Crusher run / road base | 1.5 | 3,000 |
| River rock | 1.35 | 2,700 |
| Decomposed granite | 1.3 | 2,600 |
| Sand, dry | 1.35 | 2,700 |
| Topsoil | 1.1 | 2,200 |
How deep should gravel be?
- Decorative top layer or garden beds: 2–3 in.
- Walkways and paths: about 3–4 in over a compacted base.
- Patio or paver base: 4–6 in of compacted crushed stone, plus about 1 in of bedding sand under pavers.
- Driveways: usually built in layers — a coarse base, a middle layer and a finer top layer — for a total of roughly 8–12 in on new builds. A refresh of an existing drive often needs only 2–3 in on top.
Requirements depend on soil, drainage and traffic, so follow your contractor's or supplier's recommendation for structural work.
Gravel coverage chart
Cubic yards and tons (at 1.4 tons per yard) for common areas and depths, without waste:
| Area | 2 in deep | 3 in deep | 4 in deep |
|---|---|---|---|
| 100 sq ft | 0.62 yd³ / 0.86 t | 0.93 yd³ / 1.30 t | 1.23 yd³ / 1.73 t |
| 200 sq ft | 1.23 yd³ / 1.73 t | 1.85 yd³ / 2.59 t | 2.47 yd³ / 3.46 t |
| 300 sq ft | 1.85 yd³ / 2.59 t | 2.78 yd³ / 3.89 t | 3.70 yd³ / 5.19 t |
| 500 sq ft | 3.09 yd³ / 4.32 t | 4.63 yd³ / 6.48 t | 6.17 yd³ / 8.64 t |
| 1,000 sq ft | 6.17 yd³ / 8.64 t | 9.26 yd³ / 12.96 t | 12.35 yd³ / 17.28 t |
Put another way, one ton of pea gravel covers roughly 116 sq ft at 2 in deep, 77 sq ft at 3 in, or 58 sq ft at 4 in.
Buying tips
- Bulk gravel is far cheaper than bags for anything larger than a small bed — a typical 0.5 cu ft bag holds less than 1/50 of a cubic yard.
- Ask whether the price is per ton or per yard, and enter it the same way in the calculator.
- Delivery fees often apply per load; ordering everything at once is usually cheaper than topping up later.
- Lay landscape fabric under decorative gravel to slow weeds and stop stone sinking into the soil.
Plan the whole job
Building a driveway? Our gravel driveway layers guide explains base, middle and top coats. Gravel is also the base under concrete slabs and the drainage zone behind a retaining wall; for planting beds, compare with the mulch calculator.
Frequently asked questions
How many tons of gravel do I need?
Multiply length × width (in feet) × depth (in inches) ÷ 12 ÷ 27 to get cubic yards, then multiply by the material's density. For most gravel that is about 1.4 tons per cubic yard.
How much does a yard of gravel weigh?
Most gravel weighs about 1.3–1.5 tons (2,600–3,000 lb) per cubic yard. Pea gravel and crushed stone are around 1.4 tons; crusher run is a little heavier at about 1.5 tons.
How much area does a ton of gravel cover?
At 1.4 tons per cubic yard, one ton covers about 116 sq ft at 2 in deep, 77 sq ft at 3 in, or 58 sq ft at 4 in.
How many cubic yards are in a ton of gravel?
Roughly 0.7 cubic yards for gravel weighing 1.4 tons per yard (1 ÷ 1.4 = 0.71).
How much gravel do I need for a driveway?
A new gravel driveway is typically built in layers totalling about 8–12 in. For a 50 × 12 ft driveway, a 4 in top layer alone is 7.41 cubic yards, or about 10.37 tons. Calculate each layer separately with its own depth and material.
Should I add extra gravel for compaction?
Yes. Crushed stone settles when compacted, and ground is never perfectly level. Adding about 10% is a sensible default; use more for road base that will be compacted heavily.
Sources & standards
This calculator's formulas and default values are based on the following codes, standards and published data. Codes are adopted and amended locally, so check with your building department for permitted work. See how we build and check our calculators.
- FHWA / South Dakota LTAP, Gravel Roads Construction & Maintenance Guide: layer depths, crown and drainage.
- Aggregate suppliers' published bulk densities: roughly 1.3–1.5 tons per cubic yard for common dry crushed stone and gravel, varying with type, quarry and moisture.
- Unit conversion: cubic yards = sq ft × depth (in) ÷ 324.