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If you’re not sure whether No. 57 stone is right for your project, you’re in good company. You’re standing at the quarry yard, a supplier waiting on the other end of the counter, and you’ve just been asked: “What size are you looking for?” You heard it mentioned somewhere online, but you’re not sure if it’s the right call for what you’re building. That uncertainty is exactly where mistakes happen, and they usually show up as a French drain that doesn’t drain or a driveway that turns into a muddy mess after the first hard rain.
No. 57 stone is one of the most widely specified aggregates in residential and light commercial construction. It shows up in driveways, French drains, concrete mixes, foundation drainage systems, and septic leach fields. Its popularity isn’t accidental: the stone’s physical properties make it genuinely useful across a wide range of applications. This guide covers what it actually is by spec, where it performs best, how to choose between washed and unwashed, and how to estimate the tonnage before you pick up the phone.
What No. 57 stone actually is
The official gradation in plain English
No. 57 is not a brand name or a quarry-specific product. It’s a size classification defined under ASTM D448 and AASHTO M43, which means every supplier using that designation is working from the same sieve gradation. Most particles fall between 3/4 inch and 1.5 inches, with 95 to 100 percent passing a 1-inch sieve and 0 to 10 percent passing the No. 4 sieve (4.75 mm) per ASTM D448 / AASHTO M43. That last number is the one that matters most for how this stone behaves on the job.
The full sieve breakdown looks like this:
| Sieve Size | Percent Passing |
| 1 1/2 in. | 100% |
| 1 in. | 95-100% |
| 1/2 in. | 25-60% |
| No. 4 sieve | 0-10% |
| No. 8 sieve | 0-5% |
That near-zero fines content is what separates this stone from dense-grade options. While No. 57 is technically produced as a blend of nearby sizes per AASHTO M43 / ASTM D448 practice, it behaves as a nominally open-graded aggregate, particles are roughly uniform in size, which creates consistent void space throughout any layer you place. For reference to the official tables and gradation, see the AASHTO 57 stone specs.
What “open-graded” means for your project
Because there is almost no dust or fine material, the stones stack on top of each other without filling the gaps between them. Those gaps are exactly what the stone is valued for. Compare that to crusher run, a dense-graded mix that includes everything from 3/4-inch stone down to fine dust. Crusher run compacts into a firm surface; No. 57 stone stays loose and permeable. Both have a role, but they are not interchangeable, and choosing the wrong one for a drainage application is a costly mistake.
Why drainage is where No. 57 stone earns its reputation
How void space moves water
Open-graded particles create substantial void space, commonly reported in geotechnical practice as a significant portion of total volume compared with dense-graded materials. When water enters that stone layer, it has a clear, unobstructed path to travel downward and away from the structure. There is no fine material to absorb it, slow it, or hold it near the surface. That physics makes this aggregate the standard choice behind retaining walls, under slabs on wet sites, and in any trench designed to carry water away from a foundation or yard.
The drainage capacity doesn’t just perform on day one. As long as the stone is protected with filter fabric and the surrounding soil doesn’t migrate into the voids, the permeability stays high for years. That long-term performance is the reason engineers and contractors continue specifying it over cheaper alternatives.
Where it fits in a layered drainage system
In a typical residential French drain, the cross-section follows a consistent sequence: a trench lined with geotextile filter fabric, a perforated pipe laid at the bottom (with perforations oriented to encourage inflow, commonly downward-facing in many installations), No. 57 stone surrounding and covering the pipe, and the fabric folded over the top before backfilling. The stone’s job is to move water quickly toward the pipe while the fabric keeps soil out of the voids. Pull the fabric out of that equation and the stone clogs over time; swap the aggregate for a dense-grade material and the drainage capacity drops immediately. For detailed sizing and installation guidance, see the French Drain Gravel: Right Type, Size & How Much to Order guide.
The same principle applies to foundation drain systems and septic leach fields. The stone provides the void space that allows water to infiltrate or flow, and the uniform particle size ensures those voids stay consistent throughout the bed. The aggregate choice is the reason these systems either perform well for decades or fail within a few years.
Washed vs. unwashed No. 57 stone: which fits your project
What the washing process actually removes
Washed No. 57 stone went through a rinse process at the plant that stripped off the crusher dust and residual fines. What comes off the conveyor is clean stone with fully open voids. Unwashed material still carries a coating of fine particles from the crushing process. Both are classified as open-graded aggregate, neither compacts into a smooth, dense base the way crusher run does. The difference in fines content, however, changes how each one performs under specific conditions.
For long-term drainage, washed stone is clearly the better choice. The voids stay open because there is nothing left to migrate into them over time. Unwashed stone starts with partially filled voids, and as those fines settle and surrounding soil works its way in, drainage capacity slowly decreases. That degradation may take years, but it is why engineers specify washed stone for any application where drainage is the primary function.
Matching the option to the job
Washed No. 57 stone is the right call for French drains, foundation drainage, and septic leach fields. Any time you need sustained, long-term drainage, the cleaner stone wins. Unwashed gives slightly more initial stability, which can be useful under utility trench backfill or as a base layer where a modest lock-up is acceptable and drainage is secondary. If drainage comes first, choose washed. If you need a bit more stability in a base application, unwashed works and typically costs a little less.
The best uses for No. 57 stone
Driveways and parking pads
No. 57 crushed stone is a reliable driveway material for one main reason: the angular edges interlock under vehicle weight. Rounded gravel like pea stone rolls and displaces; angular No. 57 locks together and holds its position. It also sheds water instead of trapping it near the surface, which prevents the frost heave and soft spots that plague driveways built on poorly drained subgrade. For a broader comparison of driveway aggregates and layers, see the Best gravel for driveways: Types, Layers, and Costs Guide.
For a light residential driveway on stable ground, 4 inches of compacted stone is a common contractor starting point. On soft or wet subgrade, that typically moves to 6 inches, and laying geotextile fabric between the subgrade and the stone helps prevent mixing. Note that local conditions and any applicable specifications may require different depths, always confirm with your contractor or local DOT guidance. The stone works well as a standalone top surface or as a base course under a finer finish material like No. 8 or No. 9 aggregate.
French drains and foundation drainage
This is the application where No. 57 stone is almost universally specified. A residential French drain commonly runs 12 to 18 inches deep, with the perforated pipe sitting in the bottom 4 to 6 inches and the stone filling the trench above it to within a few inches of grade, though required dimensions vary with site conditions and design. For a 50-foot drain trench that is 12 inches wide and 12 inches deep, you’re looking at roughly 2 to 3 tons of stone depending on trench geometry. That number adds up quickly, and estimating short means a second delivery charge at exactly the point in the project when you don’t have time to wait.
Concrete aggregate and base layers
No. 57 stone is also a standard coarse aggregate in concrete mix design. When a ready-mix plant specifies 3/4-inch coarse aggregate, they are typically referring to this size range. Contractors also use it as a subbase under concrete flatwork because it provides a stable platform while still allowing moisture that wicks up from the subgrade to drain away rather than accumulate. Pouring a slab directly over compacted soil with no drainage layer leaves moisture with nowhere to go. A 4-inch bed of No. 57 stone under the slab solves that problem without adding significant cost.
For additional perspective on common applications and installation uses, see this overview of the uses of No. 57 limestone.
Estimating how much No. 57 stone you need
Coverage math at common depths
The core numbers are straightforward. At a 2-inch depth, one ton covers roughly 100 square feet. At 4 inches, that drops to about 50 square feet per ton. At 6 inches, plan for approximately 33 square feet per ton. These figures are based on a bulk density of approximately 1.45 tons per cubic yard, which is a standard estimating value for crushed limestone including No. 57 size. Granite runs slightly heavier at approximately 1.50 tons per cubic yard — adjust accordingly if your supplier sources from
granite quarries. Actual density can vary ±10% by stone source, gradation, and moisture content.
Here’s a quick example. A French drain trench that is 12 inches wide, 12 inches deep, and 50 feet long holds about 50 cubic feet of stone. Divide by 27 to get cubic yards: that’s roughly 1.85 cubic yards. Multiply by 1.45 tons per cubic yard (standard limestone estimating density) and you need about 2.68 tons for the stone fill alone, before any waste factor. Add 10 percent for spillage, irregular trench walls, and compaction, and your order should be at least 3 tons.
Running that math before you call the supplier keeps you from guessing at the yard and ordering short. If you want a quick refresher on nominal sizes, read our guide on what size is 57 stone.
Using Crushed Stone Calculator to lock in your number before you order
Ordering short means paying a second delivery charge, which can easily add $100 or more to a small job. Ordering heavy means storing stone you don’t need until you find another use for it. Neither outcome is acceptable when the math is simple to run ahead of time.
For more details, check out our Crushed Stone Guides, or pull up our free Crushed Stone Calculator to enter your project dimensions and select the granite or limestone density preset. Both are accurate for standard No. 57 stone, and the tool returns your volume in cubic yards alongside an estimated tonnage. A 10 percent waste factor is built in automatically, so the number you see already accounts for the overage you need on irregular terrain or uneven trench walls. Run it before you call the quarry, not while you’re standing in the lot trying to do the math in your head. If you prefer an alternate calculator, the cubic yard/ton calculator is another quick option.
What No. 57 stone costs per ton in 2026
The price range you should expect
In 2026, No. 57 stone at the yard typically runs $45 to $75 per ton for the material itself, with quarry and bulk pricing often toward the lower end of that range and retail or landscape suppliers pushing higher. Delivered pricing on smaller orders commonly lands between $75 and $150 per ton equivalent once trucking is factored in. Limestone-source quarries in the Midwest and South tend to come in at the lower end. Markets farther from aggregate sources, or in higher-cost metro areas, will push toward the top. Prices vary by region, so confirm current rates with your local supplier.
What moves the number up or down
Three factors control the price more than anything else: proximity to a quarry, order size, and whether you pick up or take delivery. A full truckload, truck capacities vary, but loads commonly fall in the range of 18 to 22 tons depending on truck type and region, almost always gets the best per-ton price. Half-loads and small-quantity deliveries can push the effective cost to double the yard rate once trucking is included. If your project lands on the edge of a full load, rounding up to fill the truck is almost always the better financial decision. The incremental stone cost is lower than a second delivery charge, and you’ll have material on hand for the next project.
The bottom line on No. 57 stone
No. 57 stone is a 3/4-inch to 1.5-inch open-graded aggregate built for drainage, durable enough for driveways, and versatile enough to work as a concrete base or French drain fill. Washed is the right call for any application where sustained drainage is the goal. Unwashed is acceptable for base layers where a little more stability helps and drainage is secondary. Cost runs $45 to $75 per ton at the yard in 2026, with delivery adding significantly to smaller orders.
Before placing any order, run your dimensions through Crushed Stone Calculator using the granite or limestone preset. The tool handles the cubic yard to tonnage conversion automatically, includes the waste factor, and gives you a number you can hand directly to your supplier. Measure your area, plug it in, and you’ll have a quantity you can confirm with confidence before you commit to the order.