Paving & Walls
Paver Base and Sand Calculator
Enter the length and width of the paved area, the depth of the compacted gravel base and the bedding sand layer, and a waste allowance. You get both layers in cubic yards and tons, and the sand also in 50 lb bags.
Worked example
- Area = 192 sq ft. Gravel: 192 x 4/12 = 64 cu ft / 27 = 2.37 cu yd, plus 10% = 2.61 cu yd.
- Crushed stone weighs about 1.43 tons per cu yd: 3.73 tons.
- Sand: 192 x 1/12 / 27 plus waste = 0.65 cu yd, about 0.90 tons.
Common sizes at a glance
| Size | Gravel base | Bedding sand |
|---|---|---|
| 10 x 10 ft walk, 4 in base | 1.36 cu yd (1.94 tons) | 0.34 cu yd (0.47 tons) |
| 12 x 16 ft patio, 4 in | 2.61 cu yd (3.73 tons) | 0.65 cu yd (0.90 tons) |
| 20 x 20 ft patio, 6 in | 8.15 cu yd (11.65 tons) | 1.36 cu yd (1.87 tons) |
| 12 x 40 ft driveway, 8 in | 13.04 cu yd (18.64 tons) | 1.63 cu yd (2.25 tons) |
Two layers, two different jobs
The gravel base carries the load and drains water. It is crushed stone with mixed particle sizes that locks together when compacted. The bedding sand is a thin, even layer on top that the pavers settle into, so it only needs to be about an inch deep.
Because the layers are so different in thickness, the amounts are far apart. On the 16 x 12 ft example the gravel comes to 2.61 cu yd while the sand is only 0.65 cu yd.
Choosing the base depth
Depth depends on what will travel on the surface and how the soil behaves. A garden walk sees only foot traffic, a patio carries furniture and grills, and a driveway carries vehicles. Clay soils and cold-winter areas usually call for a deeper base than sandy, well-drained ground.
The common sizes table shows the jump: a 20 x 20 ft patio at 6 in needs 8.15 cu yd of gravel, and a 12 x 40 ft driveway at 8 in needs 13.04 cu yd. Check local practice before settling on a number.
Tons, yards or bags
Landscape yards often sell crushed stone by the ton and sand by the yard or ton, while home centers sell both in bags. We convert crushed stone at about 1.43 tons per cubic yard. Moisture changes the weight of sand, so treat the tonnage as a close estimate.
Bags make sense for small walks. For a full patio base, bulk delivery saves dozens of trips, so compare the bag count with a single truck load.
- Gravel base: crushed stone with fines, not round pea gravel
- Bedding sand: coarse, sharp sand, not fine play sand
- Joint sand between pavers is a separate, small purchase
Compaction and the second trip to the store
Depths here are compacted depths. Loose gravel shrinks when you run a plate compactor over it, which is the main reason people run short. The waste setting covers that loss and spillage, so do not set it to zero.
Also dig a little wider than the pavers so the base supports the edge. Count the paver pieces with the paver calculator, and if your project is a poured surface instead, the concrete slab calculator handles the volume.
Questions
How deep should bedding sand be under pavers?
About 1 inch is the usual target. A thicker sand layer tends to shift and leave dips, so fix low spots in the gravel instead of adding more sand.
How many 50 lb bags of sand do I need for a 12 x 16 patio?
At 1 inch deep with 10% waste, the calculator gives 36 bags of 50 lb.
Can I use the gravel figure for a driveway?
Yes, enter a deeper base. A driveway carries vehicles, so local practice and soil conditions should set the depth.
How this works: formulas and typical values are listed on our method page; every data source and its license is on sources.
Last reviewed November 2026.