Aggregate yards bill by the ton. Landscape yards sometimes quote yards. When the same project crosses both, the per-ton coverage math is what keeps your order honest — and what catches the ticket-mismatch most operators don't look for.
The gravel calculator gives you both numbers — cubic yards AND tons at the chosen type's density — so the dispatch confirmation can happen in whichever unit the supplier prefers.
Ask a SiteworkMath question
Quick answers about SiteworkMath's calculators and material take-offs — concrete yardage, topsoil + mulch volume, tile box-count, deck-surface materials. Free, no signup. Not structural-engineering or code advice — for joist / beam / footing / permit decisions, talk to a structural engineer, licensed contractor, or your local building department.
Hi, I'm the SiteworkMath assistant. I answer questions about the calculators and guides on this site — concrete yardage, topsoil, mulch, tile, and decking material math. I'm not a structural engineer or a licensed contractor; I'm a calculator built around the math that James Wu — Chicago-area flipper — uses on his own jobs. For structural decisions (joist sizing, beam spans, footing depth in your soil + climate, anything that needs a permit) talk to a licensed structural engineer or your local building department.
The per-ton coverage table
1 ton (2,000 lb) of each common type, with the cubic feet it contains and the area it covers at three common spread depths:
| Type | Cubic ft per ton | Coverage at 2″ | Coverage at 3″ | Coverage at 4″ |
|---|---|---|---|---|
| Decorative river rock | 21.05 | 126 sq ft | 84 sq ft | 63 sq ft |
| Pea gravel | 20.83 | 125 sq ft | 83 sq ft | 62 sq ft |
| #57 clean angular | 20.00 | 120 sq ft | 80 sq ft | 60 sq ft |
| Crusher run (loose) | 17.39 | 104 sq ft | 70 sq ft | 52 sq ft |
The math: cubic feet per ton = 2,000 lb ÷ density (lb/ft³). Coverage at depth = cubic feet ÷ depth-in-feet. So 1 ton of #57 at 2 inches is 20.00 ÷ (2/12) = 20.00 × 6 = 120 sq ft. Crusher run covers less area per ton than pea gravel because it's denser; more weight in the same cubic foot means fewer cubic feet per 2,000 lb.
The per-ton-per-use-case math
Coverage by typical residential use case, per ton:
- Driveway base (crusher run, 6″ loose).1 ton covers 17.39 / 0.5 = 35 sq ft of driveway. A 12 × 40 driveway (480 sq ft) needs 480 / 35 = 13.8 tons of crusher run for the base alone, before cushion. Add the 7% cushion and you're at 14.8 tons; suppliers usually round to 15 tons even.
- Driveway top (#57 clean, 2″). 1 ton covers 120 sq ft. Same 480 sq ft driveway needs 480 / 120 = 4 tons for the top dressing. Add cushion = 4.3 tons.
- Walkway (pea gravel, 3″). 1 ton covers 83 sq ft. A 3-foot-wide × 40-foot walkway (120 sq ft) needs 120 / 83 = 1.45 tons.
- French drain (#57 clean, 12″ trench). Per linear foot the trench is 1 cubic foot at 12 × 12 inches — roughly 20 linear feet of trench per ton at 100 lb/ft³ density. A 30-foot residential perimeter drain needs about 1.5 tons of #57.
- Decorative bed (river rock, 2-3″). 1 ton at 2-3″ covers 84-126 sq ft. A 200 sq ft accent bed needs 1.6-2.4 tons depending on the spread depth.
The ticket-mismatch operator opinion
The reason this math matters in practice: the supplier's per-ton invoice and the customer's per-yard expectation don't always line up cleanly, and most operators don't check.
A delivery of 5 cubic yards of #57 stone at 1.35 tons/yd³ should land at 6.75 tons on the scale. If the ticket shows 7.25 tons, the supplier is either using a higher density on their spec sheet (say 107 lb/ft³ instead of 100) OR the load was wet enough to add ~7% to the weight. Both are honest — but you should know which, because the second one costs you extra on a per-ton job.
My take: always confirm in tons even when the conversation starts in yards, because the truck-scale weight is what closes the invoice. Ask for the supplier's published density. Ask whether the load is dry or wet (rain on the stockpile, hose-down for dust control, snow). If the per-ton and per-yard numbers can't be reconciled at the published density, ask which is the actual billed unit. Tickets that show one and invoice the other are common enough to be worth catching.
The other operator habit I'd recommend: when the practical order is under 1 ton, just go bagged. The math: delivery-fee-amortized cost of a small-load aggregate order almost always exceeds the per-cubic-foot cost of bagged from a big-box. The breakeven is around 1.5-2 tons depending on delivery distance. Below that, the per-ton math is just a comparison; above that, it's the actual billing unit.
Run the math both ways
The calculator output shows both cubic yards and tons for the chosen gravel type. If the supplier prefers tons, that's the dispatch unit. If they prefer yards, that's the dispatch unit. The other number is the verification.
Where the per-ton math breaks down
- Density variance by supplier. Spec sheet densities vary by yard — the same #57 stone might be 100 lb/ft³ at one supplier and 105 at another, depending on the gradation range they use. The per-ton coverage table above uses calculator midpoints1; the spec sheet wins when there's a tiebreaker dispute.
- Compaction loss. The coverage table assumes spread depth = ordered depth. Compactable types (crusher run, road base, #3 stone) lose 15-20% volume to compaction. A ton of crusher run covers 35 sq ft at 6 inches LOOSE — but the finished compacted layer is only about 5 inches. For finished-depth math, multiply the LOOSE coverage by 0.83 (1 ÷ 1.20).
- Wet versus dry weight. Wet loads run 10-15% heavier per cubic foot than dry. If the ticket scale-weight includes meaningful moisture, your per-ton coverage will be slightly thinner than the dry table predicts.
- Settling on decorative beds. Decorative river rock at 2-inch spread settles to about 1.5 inches over the first year as the underlying soil compacts. Plan a 0.5-inch top-off if the bed is in a high-visibility location.
- Spreading inefficiency.The 7% calculator cushion covers corner-pack adjustment, edge spillage, and wheelbarrow loss. On a tight site with good access the actual waste is closer to 4-5%; on a difficult site (sloped, long haul, hand-spread) it's 10%+.
Frequently asked
How many square feet does a ton of gravel cover?
Depends on the type and the depth. At 2 inches deep: pea gravel covers about 125 sq ft per ton, #57 clean stone 120 sq ft, crusher run 104 sq ft, decorative river rock 126 sq ft. At 3 inches: roughly 83, 80, 70, 84 sq ft respectively. The math has two steps. First, cubic feet of stone per ton = 2,000 ÷ density (lb/ft³) — at #57's 100 lb/ft³ that's 20 cubic feet per ton. Second, area covered at depth = cubic feet ÷ (depth in feet), or equivalently cubic feet × 12 ÷ depth in inches. So 20 cubic feet of #57 at 3 inches deep covers 20 × 12 ÷ 3 = 80 sq ft.
How many tons of gravel are in a cubic yard?
1.28 to 1.55 tons per cubic yard, depending on type. Decorative river rock 1.28 tons/yd³, pea gravel 1.30, #57 clean 1.35, crusher run loose 1.55 (denser still after compaction). InchCalculator's published 1.4-1.7 tons/yd³ industry range covers heavier dense-graded blends and wet loads; the SiteworkMath midpoints sit at the lower end because the engine uses dry loose density. Reverse: a ton is roughly 0.64-0.78 cubic yards depending on type.
How do I convert tons of gravel to cubic yards?
Divide tons by tons-per-cubic-yard for the type. For #57 clean stone at 1.35 tons/yd³: 5 tons ÷ 1.35 = 3.70 cubic yards. For crusher run at 1.55: 5 tons ÷ 1.55 = 3.23 cubic yards. The supplier's spec sheet has the density they're using for the conversion; if the spec sheet says 105 lb/ft³ instead of 100 for #57, the yards-per-ton will differ slightly. When the per-ton ticket and per-yard math don't agree, the supplier's published density is usually the tiebreaker.
Why do gravel prices vary by ton instead of cubic yard?
Because aggregate suppliers (quarry-direct yards) bill by truck-scale weight, not load volume. Every truck that leaves the yard goes over a certified scale; the ticket is in tons. Landscape suppliers sometimes quote yards because their customers are landscapers ordering for area-based calculations (mulch, topsoil, decorative beds). When the same project crosses both supplier types, ask both to quote in the same unit and confirm at the supplier's published density. The 2026 Chicago-metro spread on crusher run is roughly $25-40 per ton or $35-50 per yard — those should multiply out at 1.55 tons/yd³ to within a couple dollars.
What's the minimum tonnage for bulk gravel delivery?
Most quarry-direct aggregate yards in the Chicago metro set a 5-yard residential minimum, which converts to 6.5-7.75 tons depending on type. Below that, smaller landscape suppliers will dispatch 2-3 yards (3-5 tons) with a $50-100 small-load surcharge. Under 1 ton, bagged from a big-box at about 50 lb per bag (0.5 cubic feet) is roughly 40 bags — practical for a small French drain or a decorative bed, impractical for anything larger. The calculator flags the threshold when your practical-order amount falls below 5 yards.
What I'd do next
- Run your job through the calculator
Yards + tons + cushion + supplier minimum, one output covering both dispatch units.
- The volume math from the start
Length × width × depth, divided by 27.
- Per-yard weight breakdown
Density by type, dry versus wet, payload limits.
- 1. InchCalculator — Gravel Calculator for the published 1.4-1.7 tons/yd³ industry range used to cross-check SiteworkMath per-type density midpoints. ↩
By James Wu. Per-type loose bulk densities (pea 96, #57 clean 100, crusher run 115, decorative 95 lb/ft³) are midpoints from supplier spec sheets cross-checked against Omnicalculator (105 lb/ft³ default) and InchCalculator (1.4-1.7 tons/yd³ range). Compaction loss range (15-20% loose-to-compacted on crusher run / road base) from NRCS Construction Specification 423 — Earthfill and Gravel Fill. Pricing references are 2026 Chicago-metro ranges and not quotes — call your local aggregate yard for the day's actual pricing. Engine logic in lib/sitework/gravel.ts. Full methodology.