E·01 · Garden and outdoors
Gravel calculator for driveways, paths and beds
This gravel calculator turns length, width and depth into cubic yards and tons of gravel, then into the bags to buy or the bulk load to order.
The plan shows the first area with its dimensions; the section below shows the depth of the layer (not to scale).
What to buy
Your measurements
0.99 m³ of gravel: 1 m³
To buy
- 1Bulk gravel, 1 m³ (1.66 t)
Estimate only: always go by what the product label says.
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Estimate only: always go by what the product label says.
How much gravel do I need?
Volume is length × width × depth. A 12 × 10 ft path with 3 in of gravel is 12 × 10 × 0.25 = 30 cubic feet, and 30 ÷ 27 = 1.11 cubic yards. The calculator adds up every area, adds an allowance (10% unless you change it) for gravel that settles and spills at the edges, then multiplies by the density to get the weight.
Dry gravel weighs about 105 lb per cubic foot (1680 kg/m³) according to the Engineering ToolBox tables, so a cubic yard is about 1.4 tons. You can change the density in the advanced options if your supplier quotes a different figure.
A worked example
In feet and inches (US). The calculator opens with a 12 × 10 ft area, 3 in deep, 10% extra, 50 lb bags.
- Volume: 30 cu ft, or 1.11 cu yd
- With 10% extra: 33 cu ft, or 1.22 cu yd
- Weight: 33 × 105 = 3,465 lb, about 1.73 tons
- In 50 lb bags: 3,465 ÷ 50 = 69.3, so 70 bags
Seventy bags is a lot of trips, so the calculator suggests 1.5 cubic yards of bulk gravel, delivered by truck.
In metres (UK and elsewhere). A 6 × 3 m path, 5 cm deep: 0.9 m³, 0.99 m³ with 10% extra, about 1.66 tonnes, or 67 bags of 25 kg. The calculator suggests 1 m³ loose, often delivered in a bulk bag.
Driveway gravel, pea gravel and crushed stone: how deep
Pea gravel for a footpath or a decorative bed needs about 2 in (4-5 cm); deeper gravel shifts underfoot. A driveway needs about 4 in (8-10 cm) of gravel on top of a compacted base of crushed stone. Under decorative gravel, a landscape fabric keeps the stones and the soil apart.
Bags or bulk
Bags of 0.5 cu ft (about 50 lb) cost more per ton but fit in a car and suit small jobs. From about 1 cubic yard up, or once you need more than about forty bags, bulk is cheaper: suppliers sell it by the cubic yard or by the ton, usually in half-yard steps, which is why the calculator rounds bulk up to the next half yard.
Common mistakes
- Entering the depth in feet. Depth goes in inches: 3, not 0.25.
- Leaving out the extra. Gravel settles and some ends up on the lawn; without an allowance you come up short.
- Using the weight of wet gravel. Wet gravel can weigh 125 lb per cubic foot: the volume is the same, the load is heavier.
- Picking pea gravel for a driveway. Round stones roll under tires; crushed stone with sharp edges locks together.
Sources
Last reviewed: October 8, 2026 · About us