A gravel calculator turns the length, width and depth of an area into the amount of stone to order. Contruva’s free gravel calculator gives you cubic yards, cubic metres, US tons and metric tonnes in one go, plus the number of bags and a delivered cost if you enter your supplier’s price. It works for crushed stone, pea gravel, river rock, sand, topsoil and mulch.
Open the free gravel calculator in your browser. No login, no email, nothing to pay.
Open the free toolThe math is simple: area × depth = volume, then volume × weight per yard = tons. Where people go wrong is mixing feet and inches, forgetting compaction, and comparing a per-tonne price with a per-yard price. This page walks through the formula, three worked examples you can check by hand, typical weights, and how Canadian yards quote bulk material.
How to use the gravel calculator
Rectangle, circle or triangle, in feet and inches or metres and centimetres.
Crushed stone, pea gravel, river rock, sand, topsoil or mulch. Each one fills in a typical weight per yard (or per cubic metre) and a starting compaction allowance. Change either to match your supplier.
Length and width, the diameter of a circle, or the base and height of a triangle. Depth goes in inches or centimetres.
Optional. Enter the bag size printed on the product, your supplier’s price per ton, tonne, yard or cubic metre, and the delivery fee.
Cubic yards or cubic metres up top, then tons and tonnes, bags, and the delivered cost before tax.
Mulch is sold by volume, not weight, so the calculator hides tons for mulch and gives you yards, cubic metres and bags only.
How to calculate gravel by hand
Every gravel calculation is the same four steps. The only trick is converting the depth to the same unit as the length and width before you multiply.
| Step | Imperial | Metric |
|---|---|---|
| Area | Length (ft) × width (ft) = sq ft | Length (m) × width (m) = m² |
| Volume | Area × depth (in) ÷ 12 = cu ft | Area × depth (cm) ÷ 100 = m³ |
| Add allowance | × (1 + compaction %) | × (1 + compaction %) |
| To order units | cu ft ÷ 27 = cu yd | Already in m³ |
| Weight | cu yd × tons per yard = tons | m³ × tonnes per m³ = tonnes |
For a circle, the area is π × (diameter ÷ 2)². For a triangle, it’s base × height ÷ 2, with the height measured square to the base. Odd shapes are easiest to split into rectangles, circles and triangles, then add the volumes.
Worked examples
Crushed stone pad, imperial
A 12 × 30 ft parking pad, 6 inches of crushed stone, with a 15% allowance for compaction.
12 × 30 = 360.
360 × 6 ÷ 12 = 180 cu ft.
180 × 1.15 = 207 cu ft, which is 7.67 cu yd or 5.86 m³.
7.67 × 1.4 tons per yard = 10.73 US tons, or 9.74 metric tonnes.
Bagged, that’s 21,467 lb ÷ 50 lb = 429.3, so 430 bags. Nobody bags a driveway, but the number makes the case for bulk delivery.
If your supplier charges $40 a ton and $150 to deliver, the calculator shows $429.33 for stone and $579.33 delivered, before tax. If they quote $60 a yard instead, the stone is $460. Those prices are only for the example; use the ones on your supplier’s sheet.
Mulch ring around a tree
An 8 ft circle of mulch, 3 inches deep, with 10% extra.
Area 50.27 sq ft · × 3 ÷ 12 = 12.57 cu ft · × 1.10 = 13.82 cu ft, or 0.51 cu yd · ÷ 2 cu ft per bag = 6.9, so 7 bags.
Pea gravel walkway, metric
A 1.2 × 10 m walkway, 10 cm of pea gravel at 1.72 tonnes per m³, with 5% extra.
1.2 × 10 × 0.10 = 1.2 m³.
1.2 × 1.05 = 1.26 m³, which is 1.65 cu yd.
1.26 × 1.72 = 2.17 tonnes (2.39 US tons).
2,167 kg ÷ 25 = 86.7, so 87.
At an example $60 a tonne plus $120 delivery.
How much does a yard of gravel weigh?
It depends on the stone, the gradation and how wet the load is. Crushed stone with fines packs tighter than washed, single-size stone, and a load that sat in the rain weighs more on the scale. These are the starting figures the calculator uses. Every one is editable, and your supplier’s number beats ours.
| Material | Tons per cu yd | Tonnes per m³ | Usually sold |
|---|---|---|---|
| Crushed stone / gravel | 1.4 | 1.66 | By the tonne or yard |
| Pea gravel | 1.45 | 1.72 | By the tonne or yard, or bagged |
| River rock | 1.35 | 1.60 | By the tonne or bagged |
| Sand | 1.3 | 1.54 | By the tonne or yard, or bagged |
| Topsoil | 1.1 | 1.31 | By the yard or in bags by volume |
| Mulch | n/a | n/a | By the yard or in bags by volume |
Published figures vary. Inch Calculator lists crushed stone at roughly 1.4 to 1.7 tons per cubic yard, and Canada Brick’s rule-of-thumb sheet uses 1.25 tons per yard for sand (both checked November 2026). That spread is why the weight field is editable. If your supplier prints a conversion on their price sheet or scale ticket, use it.
Yards vs tonnes: how suppliers sell it
Canadian aggregate yards don’t all quote the same way. Some price stone by the metric tonne because it goes over a scale, some by the cubic yard because it goes in a loader bucket, and many list both. An Ottawa-area supplier’s 2026 price sheet, for example, shows its pea stone and sands at a per-tonne and a per-yard price side by side. Landscape depots and garden centres usually sell topsoil, mulch and triple mix by the yard.
| Conversion | Value |
|---|---|
| 1 cubic yard | 27 cu ft, or 0.765 m³ |
| 1 cubic metre | 35.31 cu ft, or 1.308 cu yd |
| 1 US (short) ton | 2,000 lb, or 0.907 tonnes |
| 1 metric tonne | 1,000 kg, or 1.102 US tons |
Watch the word “ton”. In Canada a quote in tons usually means metric tonnes, which are about 10% heavier than the US short ton you’ll see on American calculators and data sheets. The gravel calculator shows both so you can match the unit on the quote. To compare a per-tonne price with a per-yard price, multiply the tonne price by the tonnes per yard: at 1.27 tonnes per yard (1.4 US tons), $40 a tonne is about $51 a yard.
How deep should gravel, soil and mulch be?
Depth drives the order more than anything else: going from 4 to 6 inches adds half again to the load. These are common starting points, not engineering specs. Clay, poor drainage and heavy vehicles all call for more.
| Use | Typical depth | Source / note |
|---|---|---|
| Mulch beds | 2–3 in (5–8 cm) | Mississippi State University Extension |
| Paver base, walkways and patios | 4–6 in (10–15 cm) compacted | Unilock installation guide |
| Paver base, driveways | 8–12 in (20–30 cm) compacted | Unilock installation guide |
| Paver bedding sand | 1 in (25 mm) | ICPI and Unilock |
| Topsoil for a new lawn | Often 4–6 in (10–15 cm) | Common guidance; go deeper over clay |
| Gravel driveway | Varies with soil and traffic | Built in layers: a compacted base, then a surface stone |
For a gravel driveway, plan the base and the surface layer separately and run the calculator once for each, because they’re usually different stone at different prices. If you’re putting pavers on top, the paver calculator works out the base, bedding sand, polymeric sand and edging for you. Concrete slabs are covered in the construction material calculator.
Compaction, waste and rounding
Loose stone takes up more room in the truck than it does once it’s been run over with a plate compactor. If you order exactly the compacted volume, you’ll come up short. The calculator adds a percentage on top of the measured volume to cover that, plus spillage and uneven subgrade.
- Crushed stone with fines (a road base or Granular A type product): starts at 15%, because it’s meant to be compacted hard.
- Sand and topsoil: 10–15%. Topsoil settles after the first rain.
- Pea gravel and river rock: 5%. Round, washed stone doesn’t pack down much.
- Mulch: 10%. It settles and breaks down over a season.
Those are the calculator’s defaults, not a standard. If you know your stone and your compactor, change them. Then round up: suppliers deliver in whole or half yards or tonnes, often with a minimum load, and a short load usually costs more per tonne than a full one. A spare half yard on site is cheaper than a second delivery fee.
If the excavation went deeper in the low spots, the gravel will follow it. Take depth readings in a few places and use the average, not the number on the plan.
From a load of stone to a quote
Once you know the tonnage, the material line on the quote is the stone, the delivery fee, and your markup. The labour side is excavation, spreading and compaction hours at your rate. The hourly rate calculator gives you that rate, and the markup calculator turns cost into price without confusing markup with margin.
If you run a landscaping or excavation crew, Contruva keeps stone, soil and mulch in a price catalog, so building a quote takes minutes and the customer can approve it and pay a deposit from their phone with online payments. Receipts and crew hours roll into job costing, so you can see whether the 10 tonnes you priced matched the 12 you actually bought. Everything is in one plan, Contruva Pro, at $249.99 CAD a month. Try it free for 7 days, no credit card needed.