Skip to main content
Gravel Calculator

Free, no sign up, works offline

Gravel Calculator

This gravel calculator works out tons, cubic yards, cubic metres, bags, truckloads and cost from the area and depth you enter, with the arithmetic behind every one of them.

Gravel calculator

Fill in what you know. The result updates as you type.

What do you want to calculate?

Changing the goal changes which fields you fill in.

Enter the area and the depth you want.

Typical starting values for this project. Adjust to match your site and your supplier.

Units
Shape of the area

Measure the full length of the gravel area.

Use the average width if the area tapers slightly.

The thickness of the gravel layer you intend to lay.

Depths shown are common starting points, not a specification. What a job needs depends on the soil, drainage, load and local practice.

Leave blank to use the typical figure for this material, or enter the density your supplier quotes.

Waste and compaction allowance

Extra material for spillage, uneven ground, cuts and the fact that loose gravel settles once it is compacted.

Bagged gravel
Cost

This is your own quote worked through, not a live local price. Delivery, fuel charges and minimums vary widely between yards.

Delivery

Capacities differ by vehicle and by what the axle weight limits allow locally. Use the figure your supplier gives you.

Supplier rules

Most yards will not sell an arbitrary quantity. Enter their minimum and increment and the order is rounded to match.

Enter your dimensions to see how much gravel you need.

Results are estimates for planning. Bulk density varies by supplier, moisture and how much the material is compacted, so confirm quantities with your supplier before ordering.

Start from your project

Each of these opens the calculator already set up for that job, with the depths and materials that suit it.

What this calculator does that a length times width box does not

Getting a volume is the easy part. Knowing what to actually order is the part that costs money to get wrong.

  • Every shape you will meet on site

    Rectangles, circles, triangles, trapezoids, rings and irregular areas you split into sections. Or skip the geometry and type in an area you already measured.

  • Tons, yards, bags and truckloads together

    Suppliers quote in tons or cubic yards, shops sell bags, and trucks carry a fixed load. You get all four from one calculation instead of converting by hand.

  • The working, shown

    Every result opens up into the steps that produced it, with the density it used and the allowance it added. Nothing here is a black box.

Common gravel types and what they weigh

Bulk density varies by source, grading and moisture. These are the typical planning figures, and every one of them is editable in the calculator.

Material Typical density Density
Pea gravel 1.35 1.25 to 1.45
#57 gravel 1.4 1.3 to 1.5
3/4 inch crushed stone 1.4 1.3 to 1.5
Crusher run 1.5 1.4 to 1.6
River rock 1.35 1.25 to 1.45
Drainage gravel 1.35 1.25 to 1.45

Coverage at a glance

How much ground one ton covers at each of the usual depths. Worked from the density above, so the numbers match what the calculator gives you.

Depth square feet square metres
1 inches 231.4 21.5
2 inches 115.7 10.8
3 inches 77.1 7.17
4 inches 57.9 5.38
5 inches 46.3 4.3
6 inches 38.6 3.58

A worked example

The same steps the calculator just ran, spelled out for a fixed scenario so you can check the arithmetic yourself.

  1. Area: 20 ft x 10 ft
  2. Depth: 2 in, converted to feet: 4 / 12 = 0.333 ft
  3. Volume in cubic feet: 200 x 0.333 = 66.7 cubic feet
  4. Volume in cubic yards: 66.7 / 27 = 2.47 cubic yards
  5. Weight at 1.4 tons per cubic yard: 2.47 x 1.4 = 3.46 tons
  6. Allowance at 10%: 3.46 x 1.1 = 3.8 tons
  7. Recommended order quantity: 3.8 tons

A quick sanity check

One cubic yard is 27 cubic feet whatever it is made of, so how far it spreads depends only on depth.

Depth square feet
2 inches 162
3 inches 108
4 inches 81

Common gravel calculation mistakes

The errors that actually change an order, not typos.

  • Entering inches as feet, or the reverse

    A depth field expecting inches given a value in feet orders twelve times too much. Check the unit next to the depth field before you submit.

  • Using the wrong material density

    Crusher run and pea gravel are not the same weight for the same volume. Pick the material you are actually buying, or enter your supplier's own figure.

  • Forgetting an allowance

    Spreading, grading and compaction all use more material than the finished depth suggests. Ordering the exact volume with nothing extra usually means a second trip.

  • Confusing cubic yards and tons

    These are a volume and a weight, and the conversion between them depends on density. Check which one your supplier is quoting before you compare prices.

  • Ignoring supplier minimums

    A yard with a minimum order or a fixed increment will round your order up regardless of what the job needs. Ask before you commit to a figure.

  • Using bagged gravel for a large bulk project

    Bags carry a high price per unit. Past a ton or so, bulk delivery is usually far cheaper even after the delivery fee.

  • Treating a driveway surface layer as the whole driveway

    A durable driveway is normally a sub base, a base and a surface, each a different material and depth. Calculating only the top layer understates the job badly.

Why does my gravel result look wrong?

The usual causes, and where to check first.

The result looks too high
Check the depth unit first, then the dimensions, then the density. Any one of the three being ten times off produces exactly this symptom.
The result looks too low
Check that the depth is deep enough for the job, that the full area is entered, and whether an allowance was applied at all.
A supplier quote does not match
Suppliers round to their own increments and often use a different density than the typical figure this calculator starts with. Enter their density to compare like for like.
The bag count seems huge
Compare the same quantity in bulk. Past a few dozen bags, bulk delivery is almost always the cheaper and easier option.
A driveway estimate seems unusually small
Check whether the job actually needs more than one layer. A single depth entered for a driveway usually covers the surface stone alone, not the base underneath it.

How to order gravel after calculating

What to ask a supplier once you have a figure.

  1. Ask whether the material is sold by the ton or by the cubic yard.
  2. Confirm the exact material name and size, not just the colour.
  3. Ask for their density figure if you want an exact conversion.
  4. Ask about a minimum order before you settle on a quantity.
  5. Ask about the delivery fee, since it rarely scales with the load.
  6. Ask what a truck actually carries, so you know how many loads you need.
  7. Round the order upward rather than down when it falls between increments.
  8. Compare bulk and bagged prices for the same quantity before deciding.

Related tools for placing the order

How it works

Three steps, no account, nothing leaves your browser.

  1. 01

    Measure the area

    Pick the shape that matches the space and enter the dimensions in feet, metres or whatever you measured in. Odd shapes get split into sections.

  2. 02

    Choose depth and material

    Set how deep the gravel goes and pick the material. Each one carries a typical density you can replace with the figure your own supplier quotes.

  3. 03

    Read what to order

    You get the exact quantity, the quantity with an allowance added, and the amount rounded up to something a supplier will actually sell you.

How to use Methodology

Built and maintained by Akash Kinkar Pandey. See the methodology for how every figure on this page is calculated.

Other calculators here

Every calculator on this site, grouped by project so you can find the one you need.

Gravel & Aggregate

Concrete

Roofing

Framing & Lumber

Fencing

Home & Yard

Frequently asked questions

Answers to what people ask most.

How much gravel do I need?

Multiply the area by the depth to get a volume, then multiply the volume by the material's density to get a weight. A 20 by 10 foot area at 4 inches deep is 200 square feet, which works out to 66.7 cubic feet or 2.47 cubic yards. In #57 stone at a typical 1.4 tons per cubic yard, that is about 3.46 tons, or roughly 3.8 tons once a ten percent allowance is added. The calculator on this page does all of that and shows each step.

How many tons are in a cubic yard of gravel?

Between about 1.25 and 1.5 tons for most gravels, with 1.4 tons per cubic yard being the figure quoted most often for washed stone such as #57. It is not a fixed conversion: it depends entirely on the density of the specific material. Crusher run runs heavier, at around 1.5 tons per cubic yard, because the fines fill the gaps between the stones. Lava rock is far lighter, at roughly 0.55. Your supplier can tell you the figure for the pile you are actually buying, and the calculator lets you enter it.

How deep should gravel be?

It depends on what the surface has to carry, and no single number covers every job. Decorative beds and paths are commonly laid 2 to 3 inches deep. A gravel driveway is usually built much deeper and in layers, often 4 to 8 inches in total. A paver base commonly runs 4 to 6 inches of compacted base before any bedding sand. These are common starting points rather than requirements: soil type, drainage, climate, the load involved and local practice all change what a specific job needs, and anything structural should follow whatever your local building department requires.

How many bags of gravel are in a ton?

Forty 50 pound bags make up a US short ton, because a short ton is 2000 pounds. That part is exact arithmetic and does not depend on the material. Bags sold by volume are different: a 0.5 cubic foot bag of a heavy crushed stone holds more weight than the same bag of lava rock, so the number of bags per ton changes with density. The calculator handles both, converting a volume labelled bag through the density you selected.

Should I order extra gravel?

Usually yes, and ten percent is the allowance most people settle on. It covers spillage during delivery and spreading, ground that is not as level as it measured, cuts and edges, and the fact that loose gravel settles once it is compacted. For a large driveway or a job with awkward edges, fifteen percent is not unreasonable. The important thing is that the allowance is visible rather than baked in, which is why the calculator shows the bare requirement, the allowance and the final order quantity as three separate numbers.

Frequently asked questions

Work out your gravel now

No sign up, no install, and the arithmetic runs in your browser.

Start calculating More Calculators