How many tons of #57 stone do I need per 100 square feet?

At 4 inches deep in place: 100 × 0.333 × 109 lb/ft³ (compacted) ÷ 2,000 ≈ 1.8 tons. Add 10% and call it 2 tons per 100 ft². At 2 inches, half that.

What's the difference between #57 and crusher run?

#57 is clean stone — uniform 3/4–1 in pieces with no fines, so water flows through it and it stays permeable. Crusher run is stone plus dust down to powder; the fines lock together under compaction into a semi-solid base. Drainage jobs want #57; load-bearing bases want crusher run.

Why does my delivery look bigger than the calculation?

You calculated in-place (compacted) volume; the truck delivers loose volume, which runs 10–15% larger for the same weight. The calculator's 'loose volume' line predicts the pile size so the delivery doesn't alarm you.

Can I compact crushed stone myself?

For paths and pads, a rented plate compactor (about $90/day) does the job in 4-inch lifts with two to four passes per lift. Driveways and structural bases are better served by a ride-on or trench roller. Never place a full 8-inch depth and compact once — it only densifies the top 4 inches.

Which stone goes under concrete slabs?

Most specs call for 4 inches of compacted #57 or crusher run as a capillary break and uniform bearing layer. Check your plans — then size the layer with this calculator and the slab above it with the concrete slab calculator.

Gravel · Crushed Stone

Crushed Stone Calculator

Angular, quarried and self-locking — crushed stone is the structural member of the aggregate family. Enter finished dimensions; the tool handles the loose-to-compacted arithmetic.

MaterialsCalc Editorial TeamConstruction Estimating EditorsJuly 15, 2026

Contents

1.Loose vs compacted: what you're really ordering
2.Worked example: French drain
3.Compaction rules that protect the estimate

Quick answer

How many tons of #57 crushed stone do I need?

A 50 ft French drain (1 ft wide × 12 in deep) needs about 3.0 tons of #57 stone with a 10% waste allowance. A 20×10 ft driveway base at 6 in of crusher run needs about 7.7 tons. Tonnage scales directly with area and depth.

Rule of thumb:: #57 stone weighs about 109 lb/ft³ compacted — roughly 1.8 tons per 100 ft² at 4 in deep.
Formula:: Tons = Area × depth × compacted density ÷ 2,000 × (1 + waste)

Crushed stone by common project

10% waste included. 'Loose volume' is what arrives on the truck — always larger than the finished in-place volume, since compaction densifies the stone. Cost varies by stone type and region; see the crushed stone cost guide.
Project	Dimensions	Stone type	Tons	Loose volume (on the truck)
French drain	50 ft × 1 ft × 12 in	#57 clean stone	3.00 tons	2.23 yd³
French drain, long run	100 ft × 1 ft × 12 in	#57 clean stone	6.01 tons	4.46 yd³
Walkway base	3 ft × 20 ft × 4 in	#57 clean stone	1.20 tons	0.89 yd³
Driveway base	20 ft × 10 ft × 6 in	Crusher run	7.69 tons	4.56 yd³
Driveway base, long run	50 ft × 12 ft × 6 in	Crusher run	23.07 tons	13.69 yd³

Loose vs compacted: what you're really ordering

Formula

Tons = in-place volume × compacted density ÷ 2,000

in-place volume: finished dimensions after compaction
compacted density: ≈109 lb/ft³ #57 · 140 crusher run

Weight is conserved through compaction — order the tons, and expect the loose pile to be 10–15% bigger than the finished layer.

This is the concept that separates clean estimates from short ones: a compacted 4-inch base consumes about 4.5 inches of delivered loose stone. The calculator reports both volumes so the takeoff, the delivery ticket, and the finished grade all reconcile. Densities by size live in the crushed stone weight guide and the density database.

Worked example: French drain

Worked example

A 60 ft French drain: trench 12 in wide × 18 in deep, 4 in perforated pipe, #57 stone throughout.

1
Trench volume
60 × 1.0 × 1.5 = 90 ft³
2
Subtract the pipe
90 − (π × 0.167² × 60 = 5.2) ≈ 85 ft³
3
Tons of #57 (drainage stone stays loose: 100 lb/ft³)
85 × 100 ÷ 2,000 = 4.25 tons
4
Add 10%
4.25 × 1.10 = 4.7 tons

Result: Order 5 tons of #57. Wrap the trench in geotextile or the surrounding soil will clog the stone in a few seasons.

Compaction rules that protect the estimate

Full application matrix in the crushed stone best uses guide.
Application	Stone	Typical section
Concrete slab base	#57 or crusher run	4 in compacted
Driveway base	Crusher run over #2	8 in in two lifts
French drain	#57 clean	Pipe + 4–6 in surround
Paver base	Crusher run + 1 in stone dust bed	4–6 in compacted
Mud control / construction access	#2 (2–3 in)	6 in, choked with crusher run

Frequently asked questions

The crushed stone series

Crushed Stone Sizes#1 through #10 and stone dust, decoded.Guide Crushed Stone WeightLoose vs compacted, by size and type.Guide Crushed Stone CostPer-ton pricing from crusher run to specialty.Guide Crushed Stone vs GravelAngular vs rounded — why it changes everything.Comparison Crushed Stone Best UsesMatching stone size to job, from French drains to bases.Guide Crushed Stone Coverage ChartCoverage per ton at every depth.Chart

Related tools & references

Gravel Calculator Driveway Gravel Calculator Gravel Size Chart Gravel Density Database Concrete Slab Calculator

Sources & references

[1]ASTM D448: Standard Classification for Sizes of Aggregate — ASTM International, 2017
[2]AASHTO M 43: Sizes of Aggregate for Road and Bridge Construction — AASHTO, 2018
[3]ASTM C29/C29M: Bulk Density (Unit Weight) and Voids in Aggregate — ASTM International, 2017

Crushed Stone Calculator

Angular crushed stone by size number. Enter finished (in-place) dimensions — the result includes the loose volume that will arrive on the truck.

Which size do I need?

The stone sizes guide decodes #1 through #10 and stone dust.

Crushed Stone Sizes