A paver patio is mostly hidden. The pavers you see sit on an inch of sand, which sits on several inches of compacted crushed stone, which is what keeps the surface flat for decades. This calculator counts the pavers from the area and paver size, then estimates every layer underneath — gravel base, bedding sand and joint sand — along with the edge restraint and how much soil to dig out.
How to use the paver calculator
- Choose US or Metric units.
- Enter the patio length and width, or a known area for odd shapes.
- Enter the paver length, width and thickness. Measure a real paver; nominal sizes are often slightly smaller.
- Enter the joint width and the extra for cuts.
- Set the gravel base depth and bedding sand depth.
- Optionally add the price per paver.
Paver formulas
The base volume includes 20% because crushed stone compacts by about that much. Tons use typical loose densities of 1.4 tons per cubic yard for base and 1.35 for sand. Joint sand is the volume of the joints over the paver thickness, plus 10%.
Worked example: a 12 × 10 ft patio
Area: 120 ft². Each 4 × 8 in paver with a ⅛ in joint covers 8.125 × 4.125 = 33.5 in², so 4.30 pavers per ft².
Pavers: 120 × 4.30 = 515.6; with 10% extra → 568 pavers.
Base, 4 in: 120 × ⅓ ft × 1.2 = 48 ft³ = 1.78 yd³ ≈ 2.49 tons.
Bedding sand, 1 in: 11 ft³ ≈ 1,100 lb. Joint sand ≈ 118 lb (three 50-lb bags).
Dig depth: 4 + 1 + 2⅜ = 7⅜ in, about 2.73 yd³ of soil. Edge restraint: 44 ft.
Waste allowance by pattern
| Pattern | Extra pavers |
|---|---|
| Running bond or stack bond, square edges | 5–10% |
| Basket weave | 5–10% |
| 90° herringbone | 10–15% |
| 45° herringbone or curved borders | 15% or more |
Herringbone patterns interlock best under vehicles but need cuts along every edge. Curved edges and circles waste the most.
Building it to last
- Excavate and compact the soil before adding base. Soft spots in the subgrade become dips in the patio.
- Compact the base in lifts of about 2–4 inches with a plate compactor, misting it lightly so it packs.
- Slope the surface about ¼ inch per foot (2%) away from the house so water drains.
- Screed the sand to an even inch with pipes and a straight board, and do not walk on it.
- Install edge restraint around every edge that is not held by a wall or slab; plastic or aluminum edging spiked into the base is common.
- Compact the pavers with a plate compactor fitted with a pad, sweep in joint sand and compact again.
For a driveway, raise the base to 8–12 inches and use thicker pavers rated for vehicles. Order bulk base and sand by the ton using the gravel calculator, road base calculator or sand calculator if your supplier quotes a different density. A raised patio edge may need a small wall; the retaining wall calculator covers that.
Frequently asked questions
How many pavers are in a square foot?
Divide 144 by the area of one paver plus its joint, in square inches. A 4 × 8 in paver with ⅛-inch joints takes about 4.3 per square foot; without joints the figure would be 4.5. Six-inch squares take about 4, and 12-inch squares about 1.
How deep should the gravel base be under pavers?
Industry installation guides call for about 4–6 inches of compacted crushed aggregate under patios and walkways and 8–12 inches under driveways. Soft or clay soils, and areas with hard freezes, often need the deeper end of the range.
How much sand goes under pavers?
A screeded bedding layer about 1 inch (25 mm) thick of coarse concrete sand. It should not be used to fix low spots in the base; a thicker sand layer shifts and ruts over time. Fine joint sand or polymeric sand goes between the pavers after they are laid.
How much polymeric sand do I need?
It depends on the joint width and paver thickness. With narrow joints, 2⅜-inch pavers use roughly 1 lb per square foot or less; the calculator estimates it from the joint volume. A 50-lb bag covers anywhere from about 25 to 75 ft² depending on the joints, so check the bag.
How deep do I need to dig for a paver patio?
Add the base depth, the 1-inch sand bed and the paver thickness. A 4-inch base, 1 inch of sand and 2⅜-inch pavers means digging about 7⅜ inches below the finished surface, plus any slope for drainage.