How to calculate gravel
Every gravel estimate starts with volume. Multiply the area by the depth to get cubic feet, divide by 27 for cubic yards, then multiply by the weight of a cubic yard of your material to get tons. Landscape supply yards usually sell by the cubic yard; quarries and many stone yards sell by the ton, so it helps to know both.
Cubic yards = cubic feet ÷ 27
Tons = cubic yards × weight per cubic yard (lb) ÷ 2,000
Worked example: a 50 × 12 ft driveway, 4 in. of #57 stone
- Area: 50 × 12 = 600 sq ft.
- Volume: 600 × 4 ÷ 12 = 200 cu ft.
- Add 10% for compaction and spread: 200 × 1.10 = 220 cu ft.
- Cubic yards: 220 ÷ 27 = 8.15 cu yd.
- Tons at about 2,700 lb per yard: 8.15 × 2,700 ÷ 2,000 = 11 tons.
In 0.5 cu ft bags, that same job would take 440 bags, which is why driveways and large patio bases are almost always bought in bulk.
Gravel types and how much they weigh
Weight per cubic yard depends on the rock, the size of the pieces and how much fine material fills the gaps. The figures below are typical for loose, dry material and are the defaults the calculator uses. Your supplier's number is always better, so use the Custom density option if they give you one.
| Material | Common uses | Typical weight per cu yd |
|---|---|---|
| Crushed stone, #57 (about 3/4 in., no fines) | Driveway middle layer, drainage, French drains, under concrete | About 1.35 tons (2,700 lb); typically 1.3–1.45 tons |
| Crusher run, road base, paver base (stone plus fines) | Compacted base for driveways, patios, pavers and sheds | About 1.5 tons (3,000 lb); typically 1.4–1.6 tons |
| Pea gravel (rounded, about 1/8–3/8 in.) | Paths, patios, play areas, decorative beds | About 1.4 tons (2,800 lb); typically 1.3–1.5 tons |
| River rock (rounded, 1–3 in. and up) | Dry creek beds, borders, decorative ground cover | About 1.3 tons (2,600 lb); typically 1.2–1.4 tons |
| Crushed concrete (recycled) | Budget driveway and road base | About 1.2 tons (2,400 lb); typically 1.1–1.4 tons |
| Sand (dry, loose) | Paver bedding, leveling, play sand | About 1.35 tons (2,700 lb); wet sand is heavier |
| Decomposed granite | Paths and patios with a firm, natural look | About 1.4 tons (2,800 lb); typically 1.3–1.5 tons |
Stone names vary by region. Crusher run is also sold as #411, ABC stone, CR-6, dense grade aggregate or "item 4." If you are not sure what to ask for, describe the job and let the yard recommend a product.
How deep should gravel be?
| Project | Typical depth |
|---|---|
| Decorative bed or ground cover | 2–3 in. |
| Walkway or garden path | 2–3 in. of compacted base plus 1–2 in. of pea gravel or decomposed granite |
| Gravel patio | About 4 in. of compacted base plus 1–2 in. of surface stone |
| Base under pavers (foot traffic) | 4–6 in. of compacted base plus 1 in. of bedding sand |
| Base under a concrete slab or shed | 4–6 in. |
| New gravel driveway | 8–12 in. total, usually in two or three layers from coarse to fine |
| Refreshing an existing driveway | 2–3 in. of new top stone |
For a layered driveway, run the calculator once for each layer and material. Soft or clay soils, heavy trucks and wet climates call for the deeper end of each range.
Why you need extra for compaction
Gravel sold by the yard is measured loose. When you spread it and run a plate compactor over it, the pieces lock together and the layer gets thinner. Clean, single-size stone such as #57 or pea gravel settles only a little. Base materials with fines, like crusher run and paver base, pack down more. The default 10% allowance covers most jobs plus spillage; for a compacted base, 15–20% is a safer cushion. Compact base layers in lifts of about 2–4 in. at a time rather than all at once.
Buying tips
- Ask how your supplier sells. If they quote per ton and you calculated yards (or the reverse), use their weight per yard to convert.
- Check the delivery limits. Ask how many tons the truck carries, whether there is a minimum load and where the driver can dump. A loaded dump truck can crack a concrete driveway or sink into a soft lawn.
- Use bags for small jobs. Bagged pea gravel, river rock and paver base are typically 0.5 cu ft, about 54 bags per cubic yard. They make sense for small beds, fire pit surrounds and repairs.
- Put fabric under decorative stone. A woven landscape fabric under pea gravel or river rock keeps stone from sinking into the soil and slows weeds.
For the rest of your project, use the paver calculator for patio pavers, the concrete calculator for a slab over your gravel base, or the cubic yards calculator for any other bulk material.
Frequently asked questions
How much does a cubic yard of gravel weigh?
Most gravel weighs about 1.3 to 1.5 tons (2,600 to 3,000 lb) per cubic yard. Clean crushed stone like #57 is around 1.35 tons, while crusher run with fines is closer to 1.5 tons. Wet material weighs more.
How many tons of gravel do I need for a driveway?
A 50 × 12 ft driveway with 4 in. of #57 stone needs about 200 cubic feet, or 220 cubic feet with 10% extra. That is about 8.15 cubic yards, or roughly 11 tons. A new driveway built up 8–12 in. in layers needs two to three times as much.
How much area does a ton of gravel cover?
At about 2,700 lb per cubic yard, one ton of crushed stone is roughly 20 cubic feet. That covers about 120 sq ft at 2 in. deep, 80 sq ft at 3 in., or 60 sq ft at 4 in.
How many bags of gravel are in a cubic yard?
There are 54 bags of 0.5 cu ft gravel in a cubic yard (27 ÷ 0.5). At roughly 50 lb per bag, that is about 2,700 lb, which is why bulk delivery is usually the better buy for more than a yard.
What is #57 gravel?
#57 is a standard size of washed crushed stone, mostly between about 1/2 in. and 1 in. with no fine dust. Because it drains well and does not compact much, it is widely used for driveway layers, drainage and under concrete slabs.
Should I order gravel by the ton or by the yard?
Either works as long as you convert correctly. Order in whatever unit your supplier uses, and ask them how much a cubic yard of their material weighs. This calculator shows both so you can compare quotes.
Add this calculator to your website
Run a blog, contractor site or supply store? You can embed this gravel calculator for free. Copy the code below and paste it into any page. It works in WordPress, Squarespace, Wix and plain HTML.