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Paver Calculator

Estimate pavers, base gravel and bedding/joint sand for a patio or walkway — metric or imperial.

This tool estimates material quantity from the dimensions and product sizes you enter. It does not design drainage slope, edging or excavation depth — see Limitations below.
Area & Pavers

m
m

For irregular shapes, split the space into shapes you can measure and add them together, or use Custom area with your own total. This calculator does not include a drawing tool.


mm
mm
mm

Enter 0 for a tight butt joint. Paver size presets are common sizes for a quick start, not a universal standard - dimensions are always shown so you can confirm or adjust them. Check your specific paver system's installation guide for the recommended gap.

A straight/stack bond layout typically involves the least cutting. Choose the waste allowance below that suits your specific layout - layout selection is guidance only and does not change the paver-count formula.

Results
Pavers Needed
ItemValue

How to Use the Paver Calculator

Choose rectangle, square, circle, triangle, trapezoid or custom area on the Pavers tab and enter your patio or walkway dimensions, then enter your paver's length and width (or pick a size preset) and the joint gap you plan to leave. Check the Base tab for compacted gravel base, the Bedding Sand tab for the levelling layer under the pavers, and the Joint Sand tab for sand swept into the gaps - all use the area and paver details from the Pavers tab. Use the Cost tab with your local prices for pavers, base, bedding sand and joint sand priced separately.

How Many Pavers Do I Need?

Divide your total area by the footprint of a single paver module - its length and width plus any joint gap you're leaving between pavers - add a waste allowance for cuts and breakage, then round up to a whole number of pavers. Every intermediate step is shown in the results: project area, module dimensions, module area, pavers before waste, waste allowance, additional pavers and the final order quantity.

Module area = (Paver length + Gap) × (Paver width + Gap) Pavers before waste = Project area ÷ Module area Additional pavers = Pavers before waste × Waste % Final order quantity = CEILING(Pavers before waste + Additional pavers)

A larger joint gap slightly reduces the number of pavers needed to cover the same area (since each paver "claims" more floor space including its share of the joint), which is why the gap is factored directly into the module. Layout/pattern selection only shows waste guidance - it does not change this formula.

Base, Bedding Sand and Joint Sand

Base material volume is your area multiplied by your compacted base depth, plus its own separate purchase allowance (not the paver waste %), then converted to weight and bags using your base material's density. Required depth depends on soil type, sub-grade preparation, climate, drainage and expected loading - it isn't prescribed here.

Base volume (before allowance) = Area × Compacted depth Purchase volume = Base volume × (1 + Base allowance %)

Bedding sand (a thin levelling layer under the pavers) and joint sand (swept into the gaps after laying) are separate materials, each with their own depth, allowance, density and bag weight - never combined into one unexplained "sand" line. Joint sand uses an independently editable joint fill depth (not automatically tied to paver thickness) and the same joint-area-fraction geometry as the paver module.

Bedding sand volume (before allowance) = Area × Bedding depth Estimated geometric joint-fill volume (before allowance) = Area × Joint area fraction × Joint fill depth

Cost Estimate

The Cost tab prices pavers, base, bedding sand and joint sand separately. Pavers use price per paver; base, bedding sand and joint sand each support multiple pricing methods (per bag, kg, tonne or m³ in metric; per bag, lb, US short ton or yd³ in imperial), filtered to your active unit system. This is a material-only estimate - excavation, edge restraint and installation labour aren't included unless priced in separately.

Worked Example

A 6m × 4m rectangular patio (24 m²) using 200mm × 100mm pavers with a 5mm joint gap and 10% waste: module area = 0.205m × 0.105m = 0.021525 m², pavers before waste = 24 ÷ 0.021525 ≈ 1,114.98, additional pavers ≈ 111.50, giving a final order quantity of 1,227 pavers. At a 100mm compacted base depth and 1900 kg/m³ density: base volume (before allowance) = 24 × 0.100 = 2.400 m³ (2,400 L), weighing 4,560kg (4.56 tonnes) before allowance. With 25mm bedding sand: bedding volume (before allowance) = 24 × 0.025 = 0.600 m³ (600 L).

Common Paver Calculation Mistakes

The most common mistake is ignoring the joint gap entirely when estimating paver count, which can meaningfully overstate the number of pavers needed on projects with wide joints. Another is applying the paver waste allowance to base or sand material, or bedding and joint sand together as one figure - all three now have their own independent allowance and calculation. For base and sand, using a generic density figure instead of your specific material's density can also throw off weight and bag estimates by a meaningful margin, since density varies by material type and moisture content.

Limitations

This calculator estimates material quantity from the dimensions, paver size and material densities you enter. It does NOT design or verify: drainage slope, sub-grade preparation, excavation depth, edge restraints, structural base requirements, vehicle loading, local building code, or installation labour. Base depth/density figures are typical planning estimates only - confirm your specific requirements against your soil conditions, local climate and paver manufacturer's guidance before ordering materials.

Frequently Asked Questions