Everything you need to order for a paver patio comes from four numbers: your square footage, your base depth, your waste percentage, and your slope. Get those four right and the rest is arithmetic. Get one wrong and you are either making a second trip for material or explaining a puddle to your spouse.
This guide covers all four with the actual formulas, plus paver counts by unit size, the specific questions people ask most (how many 12 by 12 pavers cover a 10 by 10 patio, for instance), and the slope calculation that almost nobody does before digging.
Bring a tape measure and something to write on. None of this needs software.
How to Measure Your Patio Area
Square footage is length times width. That works when the patio is a rectangle, which many are not.
- Break irregular shapes into rectangles. Divide an L shape into two rectangles, calculate each, add them. This is more accurate than trying to measure the whole thing at once and it catches mistakes.
- For a circle, multiply the radius by itself, then by 3.14. A 10 foot diameter circle has a 5 foot radius, so 5 times 5 times 3.14, about 79 square feet.
- For a curved edge, use the average. Measure the shortest depth and the longest depth, average them, and multiply by the width. Close enough for ordering.
- Measure the finished patio, not the excavation. You dig 6 to 12 inches wider on every side for edge restraint, but you order pavers for the finished dimension.
- Write the numbers down as you go. Two people measuring the same yard on different days will disagree. Whatever you write down first is what the whole order gets built on, so measure twice.
Is 16×16 the Patio or the Paver?
Worth clearing up, because this trips people up constantly when searching. A number like 16×16 or 24×24 can mean two completely different things.
- In feet, it is the patio. A 16×16 patio is 256 square feet. A 12×12 patio is 144. A 24×24 patio is 576, which is a large patio by any standard.
- In inches, it is the paver. A 16 by 16 inch paver covers 1.78 square feet. A 24 by 24 inch paver, sometimes written as 2×2, covers 4 square feet.
- How to tell which someone means. Context. If it is being sold on a pallet, it is a paver. If someone is describing their backyard, it is feet.
The confusion matters when ordering. Asking for enough pavers for a 12×12 gets you two very different quantities depending on which one you meant.
How Many Pavers Do You Need?
Divide your square footage by the coverage of a single paver. Here are the common unit sizes worked out already.
The specific questions people ask
- How many 12×12 pavers for a 10×10 patio? A 12 by 12 inch paver covers exactly 1 square foot, so 100 pavers, plus waste. Order 105.
- How many 16×16 pavers for a 10×10 patio? Each covers 1.78 square feet, so 100 divided by 1.78 is about 57 pavers. Order 60.
- How many 16×16 pavers for a 12×12 patio? 144 square feet divided by 1.78 is about 81 pavers. Order 85.
- How many 4×8 pavers for a 10×10 patio? Each covers 0.22 square feet, so about 450 pavers. Order 475.
Waste percentages
- 5 percent for straight layouts. Running bond, stack bond, anything with square perimeter cuts.
- 10 percent for herringbone at 90 degrees. More perimeter cutting, more offcuts you cannot reuse.
- 15 percent for diagonal or curved. Forty five degree herringbone, circles, or any curved edge. The offcuts pile up fast.
- Round up to whole pallets or bundles. Suppliers sell in set quantities. Rounding up is cheaper than a second delivery for eleven pavers.
One caution on the counts above. Nominal size is not exact size. A paver sold as 12 by 12 inches is usually slightly smaller so that with a joint it lays out on a 12 inch module. Always confirm the stated coverage on the pallet or the spec sheet before ordering.
How Much Base Stone and Sand?
Two conversions do all the work here.
- Cubic feet. Square footage times depth in inches, divided by 12. A 100 square foot patio with 6 inches of base is 100 times 6, divided by 12, which is 50 cubic feet.
- Cubic yards. Cubic feet divided by 27. So 50 cubic feet is about 1.9 cubic yards.
- Tons. Crushed base stone weighs roughly 1.4 tons per cubic yard, so 1.9 cubic yards is about 2.6 tons.
Worked all the way through for common sizes.
| Patio size | Square feet | Base stone, 6 in | Bedding sand, 1 in | Joint sand |
|---|---|---|---|---|
| 10×10 | 100 | About 2.6 tons | About 0.4 tons | 1 to 2 bags |
| 12×12 | 144 | About 3.7 tons | About 0.6 tons | 2 bags |
| 16×16 | 256 | About 6.6 tons | About 1.1 tons | 3 to 4 bags |
| 20×20 | 400 | About 10.4 tons | About 1.7 tons | 5 to 6 bags |
| 10 ft round | 79 | About 2.1 tons | About 0.3 tons | 1 bag |
Quantities are planning estimates. Order roughly 10 percent extra base stone to allow for compaction and spillage.
- Order extra for compaction. Loose stone compacts down. Ordering the exact calculated volume usually leaves you short by the end.
- Bulk beats bags every time. Two and a half tons of stone bought bagged can cost several times the delivered bulk price.
- Bedding sand is coarse concrete sand. Not play sand, not mason sand. The one inch layer is a setting bed, not a leveling compound.
If you want the base numbers checked against your specific depth and area rather than these standard cases, running the quantities through a base material tool catches ordering mistakes before the truck arrives, which is the only time they are cheap to fix.
Slope: The Calculation Everyone Skips
A patio should never be level. It should be flat, which is not the same thing. Flat means a consistent plane. That plane needs to tilt away from the house so water leaves.
The standard is a quarter inch of fall per foot of run. The formula is as simple as it gets: take your run in feet, divide by four, and that is your total drop in inches.
- A 12 foot patio needs 3 inches of drop. From the house edge to the outer edge.
- A 20 foot patio needs 5 inches. Which sounds like a lot and is completely invisible underfoot.
- The minimum is an eighth of an inch per foot. Use that only where a quarter inch would create a problem, such as meeting a fixed threshold.
- Every layer carries the same slope. Subgrade, base, bedding sand, and pavers all follow the same plane. You cannot correct pitch at the sand stage, because the sand is one inch everywhere.
Set it with a string line before you dig. Run a line from the house at your finished height, measure the run, mark the drop at the far end, and pull the string down to that mark. Everything you build follows that string.
Planning Tools Worth Using
- Manufacturer visualizers. Most major paver makers offer free online tools that let you try colors and patterns on a sample patio. Good for color decisions, weak for layout.
- Retailer material calculators. The big home centers publish paver and base calculators. Useful for a sanity check, though they often assume a thinner base than a freeze and thaw climate wants.
- Graph paper. Still the fastest way to test a layout. One square equals one foot, draw the furniture at scale, and problems become obvious.
- A garden hose and actual chairs. The only tool on this list that accounts for how the space feels. Use it before you finalize any dimension.
If a deck is part of the same project or the alternative to it, the estimating logic runs the same way on that side, and estimating a deck build by the numbers lets you compare the two options on cost rather than on impression.
Your Ordering Checklist
- Confirm square footage. Measured twice, written down, irregular shapes broken into rectangles.
- Pick the paver and confirm actual coverage. From the pallet or spec sheet, not from the nominal name.
- Apply the waste percentage. 5, 10, or 15 percent depending on layout, then round up to full bundles.
- Calculate base stone in tons. Area times depth divided by 12, divided by 27, times 1.4. Add 10 percent.
- Calculate bedding sand. One inch depth, same conversion. Coarse concrete sand only.
- Count perimeter feet for edge restraint. Plus spikes at roughly one per foot.
- Work out joint sand bags. Coverage varies with joint width and paver thickness. Check the bag.
- Calculate your total drop. Run divided by four, in inches, away from the house.
- Check delivery minimums and access. Bulk stone needs somewhere to be dumped that is not the middle of the driveway you need to use.
Frequently Asked Questions
How do I calculate how many pavers I need for a patio?
Divide your patio square footage by the coverage of one paver in square feet, then add 5 to 15 percent for waste depending on the pattern. A 12 by 12 inch paver covers 1 square foot, so a 100 square foot patio needs about 105 of them.
How much slope should a paver patio have?
A quarter inch of fall per foot of run, always away from the house. Divide the run in feet by four to get the total drop in inches. A 16 foot patio needs about 4 inches.
How much base do I need under a paver patio?
Six inches of compacted stone for a standard patio, eight to ten for driveways or hot tubs. For quantity, multiply square footage by depth in inches, divide by 12 for cubic feet, then by 27 for cubic yards, then by about 1.4 for tons.
How many 12×12 pavers do I need for a 10×10 patio?
One hundred, since a 12 by 12 inch paver covers exactly one square foot. Order about 105 to allow for cuts and breakage.
What is the best base for a paver patio?
Compacted crushed stone with fines, placed in 2 inch layers over geotextile fabric, topped with one inch of coarse concrete sand. Depth is 6 inches for patios in a climate that freezes.
What goes under patio pavers?
From the bottom up: compacted subgrade soil, geotextile fabric, 6 inches of compacted base stone, and 1 inch of screeded bedding sand. Pavers sit on the sand.
Is there a free paver patio design tool?
Several manufacturers offer free online visualizers for trying colors and patterns. They are genuinely useful for appearance decisions and less useful for layout, which is better tested in the yard with a hose and real furniture.
How do I measure square footage for a patio?
Length times width for rectangles. Break irregular shapes into rectangles and add them together. For circles, multiply the radius by itself and then by 3.14.
What is patio paver spacing?
Most interlocking pavers have small spacer nubs on the sides that set the joint automatically, usually around an eighth of an inch. Wider deliberate spacing, for planted or gravel joints, is a design decision that changes both your paver count and your joint material.
The Bottom Line
Four numbers run this whole project. Square footage from measuring twice, base depth of 6 inches for a standard patio, waste of 5 to 15 percent depending on pattern, and a quarter inch of fall per foot away from the house.
Do the arithmetic before you order rather than at the supply yard. A short delivery costs a weekend, and a missing slope calculation costs considerably more than that.
If the numbers come back bigger than expected and you are reconsidering the size, the smaller footprint options and what they hold will tell you what you actually lose by trimming. And if you would rather hand the arithmetic to someone else entirely, most trusted patio pros in Cincinnati will do a full material takeoff as part of quoting the job.