How to use the gravel calculator
- Enter the length and width of the area.
- Enter the depth in inches.
- Enter the weight of the stone per cubic yard. Get this figure from your supplier for the exact product; it varies with stone type, size and moisture.
- Add extra for compaction if the gravel will be rolled or tamped.
Ask your supplier how much their gravel weighs per cubic yard; Decoratoradvice uses that figure to turn volume into tons.
Gravel formula
Volume = length × width × depth × (1 + compaction extra)
Cubic yards = cubic feet ÷ 27
Weight = cubic yards × tons per cubic yard
Worked example
A path 20 ft long and 10 ft wide, 4 in deep, 10% extra, stone weighing 1.4 tons per cubic yard:
20 × 10 × 0.333 = 66.7 cu ft
With 10% extra: 73.3 cu ft = 2.72 cu yd
2.72 × 1.4 = 3.8 tons
The 1.4 tons per cubic yard is an example figure in this calculator, not a property of all gravel. Use the supplier's number.
Volume or weight?
Suppliers sell gravel by the cubic yard, by the ton, or both. Weight lets them load trucks on a scale; volume is what you spread. This calculator gives both, so you can compare quotes. In metric, gravel is sold by the cubic metre or the tonne.
Tips
- Compact gravel in layers a few inches thick for bases under pavers and sheds.
- Use a weed barrier under decorative gravel if you want to reduce weeds.
- For paver patios, the paver calculator gives base and sand volumes together.
- For a retaining wall's levelling pad and drainage stone, see the retaining wall calculator.
Common mistakes
- Using a generic weight. Crushed stone, river rock and pea gravel weigh different amounts; ask the supplier.
- No allowance for compaction. A compacted base ends up thinner than the loose depth.
- Mixing up short tons and tonnes. A US ton is 2,000 lb; a metric tonne is 1,000 kg (about 2,205 lb).
Frequently asked questions
How many tons of gravel do I need?
Work out cubic yards, then multiply by the stone's weight per cubic yard from your supplier. For 2.72 cu yd at 1.4 tons per cubic yard, about 3.8 tons.
How much area does a ton of gravel cover?
It depends on depth and weight. At 1.4 tons per cubic yard, a ton is about 0.71 cu yd, which covers about 58 sq ft at 4 in deep.
How deep should a gravel driveway be?
It depends on the soil, the base and the traffic. Ask a local supplier or contractor; driveways usually need a deeper, layered base than paths.
What is the difference between a cubic yard and a ton?
A cubic yard is volume; a ton is weight. How many tons are in a yard depends on the stone.
Can I use this for sand or crushed concrete?
Yes, with the supplier's weight for that material. For a plain volume, the cubic yard calculator works for any bulk material.
Is gravel better than mulch for beds?
They do different jobs; stone does not break down or feed the soil. For organic mulch, use the mulch calculator.
Key takeaways
- Cubic yards = length × width × depth (in feet) ÷ 27.
- Tons = cubic yards × the supplier's weight per cubic yard.
- Add extra for compaction.
- A US ton is 2,000 lb; a metric tonne is 1,000 kg.