A paver calculator works out everything that goes into a paver job from one set of measurements: the number of pavers with waste, the compacted base gravel, the bedding sand, the bags of polymeric sand for the joints, and the edge restraint. Contruva’s free paver calculator does all five for a patio, walkway or driveway, in imperial or metric, with an optional cost for each line.
Open the free paver calculator in your browser. No login, no email, nothing to pay.
Open the free toolMost paver estimates that go wrong don’t miss on the pavers. They miss on the base: it runs past the edges, it compacts, and a driveway needs roughly twice the depth of a patio. Below is the math the calculator uses, the base depths it starts from and where they come from, and a full worked example you can check by hand.
How to use the paver calculator
Patio or walkway, or driveway. The choice sets the starting base depth. Then feet and inches or metres and centimetres.
Length × width for a rectangle, which also gives the perimeter. For an odd shape, enter the total area and the perimeter yourself. Add any edge that sits against the house, a step or a curb.
4 × 8 Holland stone, 6 × 6, 6 × 9, 12 × 12 or 24 × 24 slabs, or a custom size from the spec sheet. Set the joint width and the waste.
Base depth, how far it runs past the edge, a compaction allowance, bedding sand depth, polymeric sand coverage from the bag, and the length of one piece of edge restraint.
Per square foot or square metre of pavers, per ton or tonne of base and sand, per bag and per piece.
How many pavers do I need?
Pavers per square foot is 144 divided by the paver’s face area, with the joint added to both sides. In metric it’s 1,000,000 divided by the face in millimetres. Then multiply by the area with waste and round up.
| Step | Imperial | Metric |
|---|---|---|
| Pavers per area | 144 ÷ ((width + joint) × (length + joint)), inches | 1,000,000 ÷ ((width + joint) × (length + joint)), mm |
| Area with waste | sq ft × (1 + waste %) | m² × (1 + waste %) |
| Pavers to order | Area with waste × pavers per sq ft, rounded up | Area with waste × pavers per m², rounded up |
The joint matters more than people expect on small units. A 4 × 8 Holland stone is 4.5 per square foot with no joint, but 4.30 with a 1/8 inch joint, which is about 4.5% fewer pavers.
| Paver (nominal) | Per sq ft, no joint | Per sq ft, 1/8 in joint | Per m², 3 mm joint |
|---|---|---|---|
| 4 × 8 in (100 × 200 mm) | 4.5 | 4.30 | 47.83 |
| 6 × 6 in (150 × 150 mm) | 4.0 | 3.84 | 42.72 |
| 6 × 9 in (150 × 225 mm) | 2.67 | 2.58 | 28.67 |
| 12 × 12 in (300 × 300 mm) | 1.0 | 0.98 | 10.89 |
| 24 × 24 in (600 × 600 mm) | 0.25 | 0.25 | 2.75 |
Real units are often a few millimetres off nominal, and many pavers have spacer nibs that set the joint for you. If the manufacturer publishes a coverage per square foot or per pallet for a specific paver, use the custom size or trust their number over a generic one. Pallet coverage varies too much between products for the calculator to guess, so ask your dealer how many square feet come on a pallet of the paver you’ve picked.
How much base gravel do I need under pavers?
Three things set the base: depth, how far it extends past the paving, and compaction.
| Use | Compacted base depth | Source |
|---|---|---|
| Walkways and patios (foot traffic) | 4–6 in (about 10–15 cm) | Unilock installation guide; ICPI lists 4 in (100 mm) as the minimum for pedestrian areas |
| Driveways (cars) | 8–12 in (about 20–30 cm) | Unilock installation guide |
Both checked November 2026. Go to the deep end of the range on clay, wet or disturbed soil, and ask an engineer for anything carrying trucks. The calculator starts at 6 inches (15 cm) for a patio and 10 inches (25 cm) for a driveway, and you can type over either.
The base also runs past the paved edge so the edge restraint sits on compacted stone. Unilock’s own example digs a 20 × 10 ft patio with 6 inches of base out to 21 × 11 ft, which is 6 inches past every side. The calculator does the same: base area = paved area + perimeter × overhang + the four corners, which for a rectangle is exactly (length + 2 × overhang) × (width + 2 × overhang).
Then it adds a compaction allowance (15% to start) because the stone you order is loose and the depth you need is compacted, and converts to cubic yards, cubic metres, tons and tonnes using a weight per yard you can change. For the stone itself, the gravel calculator goes deeper on weights, yards vs tonnes and how suppliers price it.
Bedding sand and polymeric sand
Pavers sit on a screeded bedding layer, not directly on the base. ICPI and Unilock both call for a 1 inch (25 mm) bedding layer, and Unilock says not to compact it before the pavers go down. The calculator works out bedding sand over the paved area only, at the depth you set, with no compaction allowance; round it up when you order.
Polymeric sand goes in the joints after the pavers are laid and compacted. How far a bag goes depends almost entirely on joint width and paver depth, so the calculator asks for the coverage printed on the bag and divides. For a sense of the range, Techniseal’s data sheet for HP NextGel lists 60 to 120 sq ft per 50 lb bag for narrow joints and 25 to 40 sq ft for wide joints (checked November 2026). The calculator defaults to 60 sq ft (5.5 m²), the low end for narrow joints, so you’re not short on the last row.
Natural stone, tumbled pavers and wide joints eat polymeric sand. If your paver has big chamfers or irregular edges, use the wide-joint figure on the bag.
Edge restraint
Every edge that isn’t held by a wall, step or curb needs restraint so the pavers don’t creep. The calculator takes the perimeter, subtracts the length you said is already held, and divides by the length of one piece. Plastic paver edging such as Snap Edge comes in 8 ft lengths, so that’s the default (2.4 m in metric). Spikes are sold separately; follow the edging maker’s spacing.
Worked example: a 12 × 16 ft patio
A 12 × 16 ft patio with one long side against the house, 4 × 8 Holland stone with a 1/8 inch joint, 5% waste, 6 inches of base running 6 inches past each edge with 15% for compaction, 1 inch of bedding sand, and polymeric sand at 60 sq ft per bag.
192 sq ft × 1.05 = 201.6 sq ft. 144 ÷ (4.125 × 8.125) = 4.30 per sq ft. 201.6 × 4.30 = 866.2, so 867.
(12 + 1) × (16 + 1) = 13 × 17 = 221 sq ft.
221 × 6 ÷ 12 = 110.5 cu ft. × 1.15 = 127.1 cu ft, or 4.71 cu yd. At 1.4 tons per yard, 6.59 US tons.
192 × 1 ÷ 12 = 16 cu ft. At 1.3 tons per yard, 0.77 tons.
192 ÷ 60 = 3.2, so 4 bags.
Perimeter 56 ft − 16 ft against the house = 40 ft. 40 ÷ 8 = 5 pieces.
Make the same pad a driveway with 10 inches of base and the stone goes from 4.71 to 7.84 cu yd. That’s the line that sinks paver quotes when it gets copied from the last patio.
The same patio in metric
A 3.6 × 4.8 m patio, 100 × 200 mm pavers with a 3 mm joint, 5% waste, 15 cm of base running 15 cm past each edge plus 15%, 2.5 cm of bedding sand, polymeric sand at 5.5 m² per bag and 2.4 m edging, with the 4.8 m side against the house.
868 pavers · base 3.9 × 5.1 m = 19.89 m², 3.43 m³ or 5.70 tonnes at 1.66 t/m³ · bedding sand 0.43 m³ (0.67 t) · 4 bags of polymeric sand · 12 m of edging, 5 pieces.
How much waste to add for pavers
| Layout | Starting waste |
|---|---|
| Running bond or stack bond, square edges | 5% |
| Basket weave, few cuts | 5–10% |
| Herringbone, 45° layouts, curves and borders | 10–15% |
| Lots of inside corners, circles or a small, cut-heavy area | 15% or more |
These are starting points, not a standard. Waste depends on the pattern, how many cuts meet the edges and how careful the crew is with the saw. Keep a few spare pavers for the customer; a patio that needs a repair in five years is easier to match from the garage than from a discontinued colour.
- Measure the finished size, not the dig. Pavers cover the paved area; base covers the dig.
- Check the perimeter on odd shapes. A curved patio has more edge than a rectangle of the same area, so more restraint.
- Buy every pallet from one run. Colour can shift between production runs.
From a material list to a quote
The material list is half the quote. The other half is excavation, hauling the spoil, base compaction in lifts, laying, cutting and sanding, at your labour rate. Use the hourly rate calculator to set that rate and the markup calculator to price the job, then send it from the free estimate generator.
If you do hardscaping every week, Contruva is built for landscaping and hardscape crews. Keep pavers, base and sand in your price catalog, build a quote in minutes, and let the customer approve it and pay the deposit online with Contruva payments. Job costing tracks the stone you actually bought against what you priced. It’s one plan, Contruva Pro, at $249.99 CAD a month. Try it free for 7 days, no credit card needed.