Blog · Landscape & Groundwork
How Much Gravel Do I Need?
Measure the area, pick a depth, turn it into cubic yards, then convert to tons for your supplier. Here is the whole process with worked numbers.
The short answer
Multiply length × width × depth (all in feet) to get cubic feet, then divide by 27 for cubic yards. Most suppliers also sell by weight, so multiply cubic yards by your gravel’s density in tons per cubic yard. A planning figure of about 1.4 tons per cubic yard is common for crushed stone and pea gravel, but the right number is the one your supplier gives for the exact product. The gravel calculator does all three steps at once.
Step 1: Measure the area
Measure the length and width of the area in feet. Split L-shaped or curved beds into rectangles and add them up, or work out the total first with the square footage calculator. Leave out anything that will not be filled, such as a shed base or a tree ring.
Step 2: Choose a depth
Depth changes the order more than anything else. These are common planning depths; your project design or local supplier may call for something different.
| Use | Common planning depth | One cubic yard covers about |
|---|---|---|
| Decorative cover, light foot traffic | 2 in | 162 ft² |
| Garden paths and walkways | 2–3 in | 108 ft² at 3 in |
| Driveways (usually built in layers) | 4–6 in in total | 81 ft² at 4 in |
Step 3: Convert to cubic yards and tons
Worked example: a garden path
A path 30 ft long and 3 ft wide at 3 in deep is 30 × 3 × 0.25 = 22.5 ft³. Divide by 27 to get 0.83 yd³. At 1.4 tons per cubic yard that is about 1.17 tons before any allowance.
Worked example: a two-layer driveway
A 12 × 40 ft driveway with a 4 in base layer and a 2 in top layer is 480 ft² of area. The base is 160 ft³ (5.93 yd³, about 8.3 tons at 1.4 t/yd³) and the top is 80 ft³ (2.96 yd³, about 4.15 tons). Order the layers separately because they are usually different stone.
Step 4: Add an allowance once
Loose stone settles when it is compacted, and bases are rarely perfectly level. Add your allowance in one place only, either by measuring a little deeper or with the extra-material field in the calculator, never both.
Which gravel calculator should I use?
- Pea gravel calculator for small rounded stone on paths and play areas.
- Crushed stone calculator for angular stone used in bases and driveways.
- River rock calculator for larger decorative stone in beds.
- Cubic yard calculator when you only need volume, for any loose material.
Before you order
- Ask whether the supplier sells by the ton or by the cubic yard, and get the density for the exact product.
- Check the minimum delivery and where the truck can tip the load.
- For a driveway or anything that carries vehicles, follow your project design for depth, layers and compaction.