Paver Calculator
Estimate everything a paving job needs from the area to cover and the size of one paver: the paver count with a waste allowance, the crushed-stone sub-base, the bedding sand, the bags of polymeric joint sand, and an optional cost breakdown. Works in metric (m, cm) or imperial (ft, in), with pattern presets that suggest the right waste.
Formula
Worked example
Imperial: a 16 × 12 ft patio is 192 sq ft. With 4 × 8 in pavers (about 0.232 sq ft each including a 3 mm joint), that is 192 ÷ 0.232 ≈ 828 pavers bare. Add 10% waste for a straight bond: about 910 pavers. The base needs roughly 3.2 tons of gravel and 0.75 tons of bedding sand, plus 3 bags of polymeric joint sand.
How the paver count is worked out
The estimate begins with the area you are paving and the footprint of a single paver. Multiplying the area length by its width gives the total surface, and dividing that by the area of one paver gives the number of pavers needed before any cutting. Because you cannot buy a fraction of a paver, the result is rounded up to the next whole unit. A 4 × 8 in brick paver covers about 0.22 sq ft, so a 192 sq ft patio needs roughly 850 pavers to reach the bare minimum. The calculator keeps the paver width and length separate, so it handles rectangular brick-style pavers and not only squares, and it converts those dimensions into the same unit as the area before dividing. If you enter a joint gap, that width is added to each paver side so the count reflects the real spacing on the ground.
Pattern presets and the waste allowance
Almost no patio divides neatly into whole pavers, so the units along the edges and around features have to be cut, and many offcuts are too small to reuse. A waste allowance adds a percentage of spare pavers to cover those cuts, the occasional breakage during delivery and laying, and a few held back for future repairs. The laying pattern drives how much waste you should expect: a straight running bond in a rectangular area typically needs about 10%, while a diagonal 45-degree or herringbone layout produces far more unusable offcuts and warrants around 20%, and tight circular or curved designs can reach 25%. Selecting a pattern prefills a sensible figure, and choosing Custom lets you set your own. Ordering the spares in the same batch protects you against the colour variation common between production runs of concrete and clay pavers.
Base, bedding sand, and joint sand
A lasting paver surface is built in layers. A compacted crushed-stone sub-base spreads the load and drains water, usually about 10 cm (4 in) for a patio and deeper for a driveway. On top of that sits a thin levelling course of sharp bedding sand, around 2.5 to 4 cm (about 1 in), which the pavers are set into. After laying, polymeric joint sand is swept into the gaps between pavers and wetted so it hardens, locking the pavers together and resisting weeds and ants. This tool estimates the gravel and bedding sand by tonnage and cubic yards (or cubic metres), since aggregate is sold by weight, and counts the bags of polymeric sand from the paved area, allowing roughly one 50 lb bag per 80 sq ft of narrow joints. Set any layer depth to zero to leave it out of the estimate.
Costing the job
Turn on the cost estimate to price the four main materials together: the pavers at a price each, the gravel and bedding sand by the tonne, and the polymeric joint sand by the bag. The calculator multiplies each quantity by your local price and adds them into a single planning figure shown in your chosen currency. Treat the total as a budget guide rather than a quote, since delivery charges, edge restraints, geotextile fabric, and labour are not included and prices vary widely by region and supplier. Confirm the layer depths and paver size against your own site conditions and any local drainage or building rules before ordering.
Common paver sizes and coverage
| Paver size | Area per paver | Per 100 sq ft | Per 10 m² |
|---|---|---|---|
| 4 × 8 in (10 × 20 cm) | 0.22 sq ft | 450 | 500 |
| 6 × 6 in (15 × 15 cm) | 0.25 sq ft | 400 | 444 |
| 6 × 9 in (15 × 23 cm) | 0.38 sq ft | 267 | 296 |
| 8 × 8 in (20 × 20 cm) | 0.44 sq ft | 225 | 250 |
| 12 × 12 in (30 × 30 cm) | 1.00 sq ft | 100 | 111 |
| 12 × 18 in (30 × 45 cm) | 1.50 sq ft | 67 | 74 |
Approximate pavers needed per 100 sq ft and per 10 m², before joints and waste.
Frequently asked questions
How much extra should I add for waste?
About 10% is a safe default for a straight running bond in a rectangular area. Increase it to roughly 20% for diagonal 45-degree or herringbone layouts and up to 25% for circular or curved designs, which generate many unusable offcuts. Selecting a pattern here prefills a typical figure, and you can override it with Custom.
Does this account for the gaps between pavers?
Yes, optionally. Enter a joint gap (usually 2 to 5 mm) and the calculator adds it to each paver side, so the count reflects the real spacing. With tight joints the effect is small, and the waste allowance comfortably covers any rounding, so leaving the gap at its default still gives a safe quantity to buy.
How much base, sand, and joint sand do I need?
Gravel sub-base and bedding sand are the paved area multiplied by each layer depth, converted to tonnes (or cubic yards). A common build is about 10 cm (4 in) of compacted gravel under roughly 2.5 cm (1 in) of bedding sand. Polymeric joint sand is estimated at about one 50 lb bag per 80 sq ft of narrow joints; wider joints or thicker pavers use more.
How deep should the base be?
For a patio or walkway, plan on about 10 to 15 cm (4 to 6 in) of compacted crushed stone with a 2.5 to 4 cm (1 to 1.5 in) bedding sand course. A driveway that carries vehicles needs a thicker, well-compacted base, often 20 cm (8 in) or more. Confirm the depth against your soil and the load the surface must carry.