How Many Paving Slabs Do I Need?
Updated June 2026 · Estimates only — verify before quoting
The number of slabs you need comes down to two things: the area you are covering and the size of each slab — plus a sensible allowance for cuts.
// Do the maths instantly
Paving Slabs Calculator
Exact slab count for any area and slab size.
Open the Paving Slabs CalculatorHow to work it out
Slabs per m² = 1 ÷ (slab length in m × slab width in m). A 600 × 600mm slab covers 0.36 m², so you need about 2.8 slabs per m². Multiply by your patio area and add 5–10% for cuts around edges and obstacles.
- 450×450mm: ~4.9 slabs per m²
- 600×600mm: ~2.8 slabs per m²
- 600×900mm: ~1.85 slabs per m²
Frequently asked questions
How many 600x600 slabs in a square metre?
About 2.8 slabs per m² (each covers 0.36 m²). Add 5–10% for cutting.
How do I work out slabs for a patio?
Divide your patio area by the area of one slab, then add a cutting allowance. The calculator below does this for any slab size.
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