Landscaping
Gravel Calculator
Work out how much gravel you need for a driveway, path, patio or drainage base. This gravel calculator turns your measurements and depth into cubic yards and tons, adds an allowance for compaction, and shows whether to buy in bulk or by the bag, with an optional cost per ton, per yard or per bag.
Result
Enter your measurements and press Calculate. What to buy, the working and the cost will appear here.
How to use the gravel calculator
- Measure each area as a rectangle or circle, or enter a known area in square feet. Add areas for a driveway plus a turnaround, or several paths.
- Enter the depth of gravel for each area. Paths are usually 2–3 in, driveways 4–6 in.
- Choose the type of gravel. Each type has a typical weight per cubic yard; if your supplier gives you a figure, enter it instead.
- Set the allowance for compaction and spillage, and the bag size if you are buying bags.
- Add a price per ton, per cubic yard or per bag, then press Calculate.
How much gravel do I need? The formula
First find the volume, then convert it to weight, because most suppliers sell gravel by the ton:
cubic yards = length (ft) × width (ft) × depth (in) ÷ 324
tons = cubic yards × tons per cubic yard
Most gravel weighs roughly 1.3–1.5 tons per cubic yard. A 20 ft × 10 ft path at 3 inches deep is 20 × 10 × 3 ÷ 324 = 1.85 cubic yards, or about 2.6 tons at 1.4 tons per yard, before any allowance.
Worked example: a gravel parking pad
A 40 ft × 10 ft parking pad beside a driveway gets 4 inches of crushed stone, with a 10% allowance for compaction. The quarry charges $45 per ton:
- Area 1: 40 ft × 10 ft = 400 ft²; × 4 in (0.33 ft) = 133.33 ft³
- With allowance: 4.938 yd³ × 1.1 = 5.432 yd³
- Weight: 5.432 yd³ × 1.35 tons/yd³ = 7.33 tons
- Bags: 146.67 ft³ ÷ 0.5 ft³ per bag = 294 bags
You need about 7.33 tons (5.43 yd³). Ordered in half-ton steps, that is 7.5 tons for $337.50. The same job in bags would be 294 bags of 0.5 ft³, which is why bulk delivery wins for anything this size. Open this example in the calculator.
How much does gravel weigh? Tons per cubic yard
Typical loose weights used by the calculator. Stone type, size and moisture all change the weight, so your supplier’s figure is always better:
| Gravel type | Per cubic yard | Metric | Allowance |
|---|---|---|---|
| General gravel (mixed sizes)A middle-of-the-range figure when the exact stone is not known. | 1.4 tons2,800 lb | 1.66 t/m³ | 10% |
| Crushed stone (#57, 3/4 in clean)Angular washed stone for drainage, driveways and bases. | 1.35 tons2,700 lb | 1.6 t/m³ | 10% |
| Pea gravelSmall rounded stone for paths, patios and play areas. Barely compacts. | 1.4 tons2,800 lb | 1.66 t/m³ | 5% |
| Road base / crusher runStone with fines that compacts firmly; allow extra for compaction. | 1.5 tons3,000 lb | 1.78 t/m³ | 15% |
How much does a ton of gravel cover?
At about 1.4 tons per cubic yard, one ton of gravel covers roughly:
| Depth | Area covered by 1 ton |
|---|---|
| 2 in | 116 ft² |
| 3 in | 77 ft² |
| 4 in | 58 ft² |
| 6 in | 39 ft² |
How deep should gravel be?
- Walkways and garden paths: 2–3 in of pea gravel or crushed stone over landscape fabric.
- Patios and seating areas: about 3 in of pea gravel, or 2 in of fines over a compacted base.
- Driveways: a compacted base of 4–8 in of road base or larger stone, topped with 2–4 in of surface gravel. Calculate the base and the top layer as two separate runs of the calculator, since they are different materials.
- Drainage and French drains: clean, washed stone such as #57, deep enough to surround the pipe.
Buying gravel: tons, yards or bags
- Bulk is sold by the ton or the yard. Quarries usually weigh loads in tons; landscape yards often sell by the cubic yard. The calculator gives both, rounded up to half units.
- Bags suit small jobs. A 0.5 ft³ bag holds about 1/54 of a cubic yard, so bags get expensive and heavy quickly. From about a cubic yard, bulk delivery is usually cheaper.
- Check the delivery. Ask about minimum loads and delivery fees, and decide where the truck can tip. A dump truck spreading the load along a driveway saves hours of wheelbarrow work.
- Mind your trailer. A cubic yard of gravel weighs well over a ton, more than many pickups and small trailers are rated to carry.
Assumptions and limitations
- Weights are typical loose figures. Wet gravel is heavier, and suppliers’ weights per yard vary.
- The allowance covers compaction and spillage. Road base and crusher run compact a lot when rolled, so use 15% or more.
- Depth is treated as even. For a crowned driveway, use the average depth across its width.
- The calculator estimates material only; grading, fabric and edging are not included.
Gravel questions
How many tons of gravel do I need?
Multiply length × width in feet by the depth in inches and divide by 324 to get cubic yards, then multiply by the weight per yard, about 1.4 tons for most gravel. Add 10% for compaction.
How many tons are in a cubic yard of gravel?
Usually 1.3 to 1.5 tons, or 2,600 to 3,000 lb. Crushed stone and pea gravel are around 1.35–1.4 tons per yard; road base with fines is closer to 1.5 tons.
How much gravel do I need for a driveway?
For a 50 ft × 10 ft driveway with 4 inches of gravel: 50 × 10 × 4 ÷ 324 = 6.2 cubic yards, about 8.6 tons at 1.4 tons per yard, plus 10–15% for compaction. A new driveway usually also needs a thicker base layer underneath.
How many bags of gravel make a cubic yard?
54 bags of 0.5 cubic feet, or 27 bags of 1 cubic foot. Bags are convenient for small areas, but a cubic yard of bagged gravel costs far more than the same amount in bulk.
How much area does a cubic yard of gravel cover?
About 162 ft² at 2 inches deep, 108 ft² at 3 inches and 81 ft² at 4 inches. The cubic yard calculator has a full coverage chart.
Formulas, unit conversions and default values are explained on our methodology page. Results are estimates; check manufacturer data and local codes before you buy or build.