A paver patio is three layers: a compacted crushed-stone base, a thin bed of sand, and the pavers themselves. This paver calculator sizes all three. Enter the patio dimensions and the face size of your paver and it returns how many pavers to buy including waste, how many pavers cover a square foot, and how much base gravel and bedding sand to order in cubic yards and tons.
The defaults follow the layer thicknesses in the Concrete Masonry & Hardscapes Association's (CMHA, formerly ICPI) Tech Spec 2 for pedestrian areas: a compacted aggregate base of at least 4 inches over well-drained soil and a 1-inch bedding sand layer. For walls around the patio, see the retaining wall block calculator; for an irregular patio, add up the sections with the square footage calculator first.
How to use the paver calculator
- Enter the length and width of the patio or walkway. For odd shapes, enter the total area as length × 1 ft.
- Enter the paver's face dimensions (length × width) as listed by the manufacturer. Thickness does not affect the count.
- Choose a waste allowance: about 5–10% for straight running or stack bond, more for herringbone, diagonal layouts and curves with many cuts.
- Set the base depth: at least 4 inches for patios and walks on well-drained soil, more on clay or for driveways.
- Keep 1 inch of bedding sand and about 15% extra for compaction of both layers.
Formula
Tons use 1.4 tons/yd³ for crushed stone and 1.35 tons/yd³ for sand, typical dry values. Joint widths of 1/16–3/16 inch are ignored because they barely change the count; many pavers have built-in spacer nibs.
Worked example
A 12 × 12 ft patio using 4 × 8 inch pavers, 10% waste, a 4 inch base and 1 inch of sand, with 15% extra on base and sand.
- Area: 12 × 12 = 144 ft².
- Each paver: 4 × 8 = 32 in² = 0.222 ft², so 4.5 pavers per ft².
- Pavers: 144 ÷ 0.222 = 648, plus 10% = 712.8, so buy 713 pavers.
- Base: 144 × 4 ÷ 12 = 48 ft³ = 1.78 yd³, plus 15% = 2.04 yd³ ≈ 2.86 tons.
- Sand: 144 × 1 ÷ 12 = 12 ft³ = 0.44 yd³, plus 15% = 0.51 yd³ ≈ 0.69 tons, or 28 small bags.
- At an illustrative $0.75 per paver, the pavers cost about $534.75.
Pavers per square foot by size
| Paver face size | Pavers per ft² (no waste) |
|---|---|
| 4 × 8 in (holland / brick paver) | 4.5 |
| 6 × 6 in | 4.0 |
| 6 × 9 in | 2.67 |
| 12 × 12 in | 1.0 |
| 16 × 16 in | 0.56 |
| 12 × 24 in | 0.5 |
Pavers per ft² = 144 ÷ (length × width in inches). Multi-size pattern kits are sold by coverage per pallet or bundle instead; use the manufacturer figure for those.
Base depth guidance
CMHA Tech Spec 2 calls for compacting the aggregate base in lifts and screeding the bedding sand to a consistent 1 inch, without using sand to fill low spots. Pedestrian areas over well-drained soils start at a 4 inch minimum base; vehicular areas, frost-prone climates and clay soils need thicker bases. When in doubt, ask your paver manufacturer or a certified installer for a section suited to your soil.
Caveats and assumptions
- Patterns matter: herringbone and 45° layouts generate more cut waste than running bond, so raise the waste figure to 15% or more.
- Border or soldier courses use different pieces. Subtract the border area and count those pavers separately along the perimeter length.
- Densities for gravel and sand are typical values; suppliers may quote different weights.
- Edge restraints, geotextile and polymeric joint sand are not included in this estimate.
Frequently asked questions
How many pavers do I need for a 12 × 12 patio?
With 4 × 8 inch pavers, 144 ft² × 4.5 = 648 pavers, or about 713 with 10% waste. Larger pavers need fewer: 12 × 12 inch pavers need 144, or about 159 with 10% waste.
How much base do I need for pavers?
Multiply the area by the base depth in feet and divide by 27. A 144 ft² patio with a 4 inch base needs 1.78 yd³, or about 2.04 yd³ with a 15% compaction allowance.
How much sand goes under pavers?
About 1 inch of coarse bedding sand, screeded flat. That is 0.44 yd³ per 144 ft², plus a little extra. Joint sand is separate.
How much extra pavers should I buy?
Typically 5–10% for straight patterns and 10–15% or more for herringbone, diagonals and curves. Keeping a few spares from the same batch makes future repairs easier to match.
Can I lay pavers directly on sand?
Installation guides do not recommend it for patios: sand alone shifts and settles. A compacted crushed-stone base under the sand is what keeps pavers level.
Sources
- CMHA — Tech Spec 2: Construction of Interlocking Concrete Pavements — base and bedding layer guidance
- CMHA — Pavers on Aggregate Base guide specification — installation specification
- NIST — Unit Conversion — area and volume conversions
This calculator gives estimates for planning and education. Check measurements, local codes, supplier specs and your school's official policy before relying on a result. See our disclaimer and how we build and check calculators.