Paver Calculator

How to use this calculator

1. Measure the patio length and width (split curves and L-shapes into rectangles).
2. Enter the paver size and joint width; most concrete pavers have built-in spacer nibs.
3. Set waste: 5% for straight runs, 10% for herringbone, 15% for curves and circles.
4. Set the sub-base depth for your use and soil; driveways need much more than patios.
5. Use the base and sand tonnage to order from a builders' merchant.

Method & assumptions

Pavers = Area ÷ ((Paver L + Joint) × (Paver W + Joint)) × (1 + waste %)
Sub-base = Area × Base depth (× ~2.0 t/m³ compacted)
Bedding sand = Area × Sand depth (× ~1.6 t/m³)

Joint

gap between pavers, often 2–5 mm / ⅛ in

Sub-base

compacted crushed stone (US paver base, UK MOT Type 1, AU road base)

Assumptions & limits

• Densities are typical; ask your supplier.
• Edge restraint is the full perimeter — reduce it where the patio meets a wall.
• Driveways and poor soils may need geotextile and deeper base — follow manufacturer guidance.

Rounding: purchase quantities are always rounded up to whole bags, boxes, sheets or bundles. See our methodology.

Worked examples

In depth: pavers planning notes

The layers under a paver patio

A paver patio is a system. On top is the paver surface, sitting on a bedding layer of sharp sand or fine screenings — usually about 1 in (25–30 mm) screeded flat. Under that is a compacted sub-base of crushed stone, typically 4 in (100 mm) for patios and paths and 6–8 in (150–200 mm) or more for driveways and poor soils. The edges are held by restraint — a concrete haunch or plastic or metal edging — so the pavers cannot creep.

The calculator estimates all three: pavers by count, sub-base by volume and weight at a compacted density of about 2.0 t/m³, and bedding sand at about 1.6 t/m³. Compaction is important: lay and compact the sub-base in layers of 2–3 in (50–75 mm) with a plate compactor.

Paver size, pattern and waste

Paver count depends on the face size plus the joint. Many concrete pavers have spacer nibs that set a joint of about 2–3 mm, while clay pavers are often laid with a 3 mm sand joint. Patterns change the waste: running bond and stack bond need 5–10% extra, herringbone and circular patterns 10–15%, because the edges are full of angled cuts.

Mixed-size patterns sold as "random" or "multi-size" packs are sold by area, not count, so use the area result. Buy pavers from a single production batch if possible, and mix from several pallets as you lay to blend any colour variation.

Fall is essential so water runs off — typically about 1:60 to 1:80 (around ⅛–¼ in per foot) away from the house. Joint sand is brushed in after compaction; polymeric sand reduces weeds and washout but must be installed exactly as the manufacturer says.

Tips & common mistakes

• Slope the patio away from buildings — about 1:60 to 1:80 (¼ in per foot is a common US rule).
• Compact the sub-base in layers with a plate compactor; most patio failures start below the pavers.
• Order 5–10 spare pavers from the same batch for future repairs.

Sources

1. ICPI – Interlocking Concrete Pavement Institute — checked 2026-10; verify before launch
2. Interpave (UK) – precast concrete paving guidance — checked 2026-10; verify before launch
3. Belgard – paver installation guide — checked 2026-10; verify before launch

Default values (bag yields, coverage rates, densities) are typical figures from manufacturer literature. Always check the label on the product you buy.

Cite or embed this calculator

DIYCalcLab. “Paver Calculator.” Oct 18, 2026. https://diycalclab.com/landscaping/paver-calculator/

An embeddable version for blogs and contractor sites is planned.