This calculator is for planning purposes only. Tonnage is an estimate — gravel density varies with moisture, stone source, and compaction. Always confirm weight with your supplier before ordering.
Free gravel calculator

Gravel Calculator: How Much Gravel Do I Need?

Enter your area length, width, and depth, pick your material type, and get cubic yards, tons, 50 lb bag count, and a bulk-vs-bagged cost comparison — instantly, with no sign-up.

Project Dimensions

Tons needed
Cubic yards
Tons to order (rounded up)
50 lb bags (retail)
Total weight

How the math works

Step 1 — volume in cubic yards

cu yd = (length_ft × width_ft × depth_in) ÷ 324

324 = 27 cu ft/yd × 12 in/ft. A canonical landscaping shortcut: multiply area by depth (in inches) and divide by 324.

Step 2 — apply waste / compaction allowance

cu yd (with waste) = cu yd × (1 + waste % ÷ 100)

The waste allowance inflates both tonnage and bag count — you buy the waste-inclusive amount.

Step 3 — tons

tons = cu yd × density (ton/yd³)

Material densities (US short tons per cubic yard): pea gravel 1.35, #57 stone 1.40, paver base 1.40, river rock 1.30, crusher run 1.40. Confirm exact weight with your supplier — density varies with moisture and stone source.

Step 4 — retail bags

bags = ⌈ cu yd × 54 ⌉

A standard 50 lb bag holds 0.5 cu ft. One cubic yard = 27 cu ft ÷ 0.5 = 54 bags.

Tools to spread and contain gravel

As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links; the price you pay is the same and it helps keep this tool free.

Under the stone

VEVOR 4×100 ft Woven Landscape Fabric (5.8 oz)

Gravel laid straight on soil sinks and grows weeds. A heavy woven geotextile underneath keeps the stones up and the weeds down — lay it before you spread to the depth you calculated.

~$37on AmazonCheck price →
Stop the ruts

GP GLOBAL TerraBrace Gravel Grid Panels

For a driveway or path, a honeycomb grid locks the gravel so it cannot rut or migrate — the depth and compaction you planned hold far longer.

~$70on AmazonCheck price →
Haul the tons

True Temper 6 cu-ft Steel Wheelbarrow

Bulk gravel is delivered in a pile; a 6 cu-ft steel barrow is how you move tons of it to where the calculator says it goes.

~$230on AmazonCheck price →
Screed it flat

True Temper 16-Tine Bow Rake

The straight back edge screeds gravel to a uniform depth before compaction, so the tonnage you bought spreads across the area you measured.

~$35on AmazonCheck price →
Compact the base

VEVOR 6.5 HP Vibratory Plate Compactor

Gravel only reaches its rated load once compacted — a plate compactor does in minutes what hand-tamping never finishes, and pays for itself versus repeat rentals.

~$430on AmazonCheck price →
Top-up by the bag

NorthRock Pea Gravel, 50 lb Bag

For a small patch or top-up where a bulk delivery makes no sense, a bagged 50 lb option covers the gap the calculator flagged.

~$61on AmazonCheck price →
Contain the gravel

EasyFlex No-Dig Edging, 100 ft

Loose gravel walks out of its bed without an edge. A flexible no-dig border keeps the stone — and the depth you paid for — where you put it.

~$45on AmazonCheck price →

Why icons, not product photos? Amazon only allows their product images through the Product Advertising API, which unlocks after the first few sales. Until then these cards use our own graphics (no scraped images = no ToS risk) and swap to live photos & prices automatically once the API is on.

Frequently Asked Questions

How do I calculate how much gravel I need?

Multiply your area length (ft) × width (ft) × depth (in), then divide by 324. That gives cubic yards. For example, a 20 × 10 ft area at 4 in deep is 200 × 4 ÷ 324 ≈ 2.47 cu yd. The divisor 324 = 27 cu ft/yd × 12 in/ft — the standard landscaping shortcut.

How many tons of gravel do I need?

Multiply your cubic yards by the material density: pea gravel is 1.35 ton/yd³; crushed #57 stone is 1.40 ton/yd³; paver base and crusher run are 1.4 ton/yd³; river rock is 1.3 ton/yd³. So 2.47 cu yd of pea gravel = 2.47 × 1.35 ≈ 3.33 tons. Always confirm density with your supplier — it varies with moisture and source.

How many 50 lb bags of gravel equal one cubic yard?

A standard 50 lb bag holds 0.5 cu ft. One cubic yard = 27 cu ft ÷ 0.5 = 54 bags. For smaller projects under half a cubic yard, bags are convenient; above that, bulk delivery is almost always cheaper.

How deep should gravel be?

Depth depends on use: 1–2 in for decorative topdressing, 2–3 in for garden paths, 4 in for driveways (surface layer), 6 in for heavy driveway base or paver sub-base. Use the waste allowance (10–15%) to account for spreading and compaction losses.

What is the compaction / waste allowance for?

The 10% default allowance (set to 15% for driveways and compacted bases) accounts for material that spills, settles into voids, or compacts lower than the initial loose depth. It inflates both your ton order and bag count — you buy the waste-inclusive amount.

What is the difference between pea gravel and crusher run?

Pea gravel (3/8") is smooth and round — ideal for decorative beds and paths but does not compact. Crusher run (dense-grade) contains fines that lock together when compacted, making it the right choice for driveway bases, shed pads, and paver sub-bases. Both are 1.35–1.4 ton/yd³ but behave very differently under load.

Is bulk delivery or bagged gravel cheaper?

At roughly 54 bags per cubic yard and about $6/bag, bagged gravel costs ~$324/yd³. Bulk delivery typically runs $30–$60/yd³ depending on your region and stone type — roughly 5–10× cheaper by volume once you exceed about 0.5–1 cubic yard. For small touch-up projects, bags win on convenience.