Gravel calculator

How to measure it on site

Gravel is sold by the ton or by the cubic yard, and the two are connected by the material's density. Measure the area and the finished depth, then decide which layer of the job you are buying for.

1. 01

   Measure the area in simple rectangles. A driveway is rarely one clean rectangle. Break it into rectangles, add them, and keep the total in square feet. A 20 × 20 pad is 400 sq ft; two 10 × 40 strips are 800.

2. 02

   Separate the layers. A driveway is three layers: a 4–6 inch base, a middle layer, and a 2–3 inch top dressing. Calculate each layer at its own depth rather than applying one figure to the whole build-up.

3. 03

   Use the compacted depth. Loose gravel settles by roughly 20 percent under compaction. If you want 4 inches in place, plan on about 5 inches loose, or the finished layer will come up short.

4. 04

   Confirm the material and the sales unit. Crushed stone, pea gravel, river rock, and crusher run have different densities, and a supplier may quote tons while another quotes yards. Check which unit the price is based on before comparing.

Common mistakes

Gravel is heavy and cheap per ton but expensive to deliver twice. These five errors cause most of the short orders.

• Calculating the whole driveway at one depth. Treating a three-layer build-up as a single 8 inch pour overstates the top dressing and understates the base. Calculate each layer separately, then add the tonnage.
• Ignoring compaction. Loose gravel loses about a fifth of its volume when compacted. Ordering the finished depth as loose material leaves a layer that is visibly thinner after the plate compactor runs.
• Assuming every gravel weighs the same. Density runs from about 1.35 to 1.50 tons per cubic yard depending on the stone. River rock and pea gravel are lighter than crusher run, so the same volume is fewer tons.
• Confusing short tons with metric tonnes. A short ton is 2,000 lb; a metric tonne is about 2,204 lb. The difference is roughly 10 percent, which matters on a multi-ton order and is easy to miss on a quote.
• Forgetting the bags-to-bulk break point. A 50 lb bag holds about 0.025 cubic yards. Once the order passes a couple of yards, bag counts climb into the hundreds and bulk delivery becomes the practical choice.

Worked example

What this calculator doesn't cover

This calculator converts area and depth into volume, tonnage, and bag counts. It does not cover these cases:

• —Compaction and subgrade preparation — the 20 percent settlement figure is a planning allowance, not a substitute for proper base work.
• —Drainage design — slope, French drains, and outlet placement decide whether water leaves the site.
• —Delivery access and load limits — a full truck may not fit a narrow drive, and some suppliers cap the load by weight.
• —Mixed or recycled materials — recycled concrete and blended aggregates vary in density more than the standard categories.

Reviewed November 2026. Sources: Aggregate volume-to-weight reference (Quikrete); Aggregate density and unit conversion reference (ASTM International). Full methodology.

How the math works

Frequently asked questions

How many tons of gravel are in a cubic yard?

On average, one cubic yard of gravel weighs approximately 1.4 US short tons (2,800 lbs). The exact weight depends on rock type and compaction: dense crushed stone #57 weighs about 1.45 tons/yd³, river rock weighs around 1.35 tons/yd³, and dense graded base (crusher run with stone dust) weighs up to 1.5 tons/yd³.

How deep should gravel be for driveways and walkways?

For pedestrian walkways and patio bases, 2 to 3 inches of gravel is ideal. For standard residential driveways, plan on 4 inches of surface gravel over a 4 to 6-inch compacted crushed stone base to support vehicle weight without rutting.

Should I buy gravel in 50 lb bags or bulk delivery by the ton?

Under about half a ton (20 bags of 50 lb) bagged gravel is the practical call — you can carry it and you don't need to schedule a delivery. Past roughly a ton (40 bags) bulk takes over, because a landscape yard or quarry sells you one truckload instead of forty individual bags, and it removes the same number of bag lifts between the driveway and the hole. Have the delivered total quoted on your exact yardage rather than comparing a shelf price per bag against a rate per ton; the calculator returns tons and the matching 50 lb bag count from the same volume, so you can compare like for like.

Do I need landscape fabric under gravel?

Yes. High-quality non-woven geotextile landscape fabric prevents the gravel from sinking into the subsoil over time, prevents mud from bubbling up, and stops stubborn weeds from taking root from beneath.