Calculator
Gravel Calculator: Cubic Yards and Tons
Last reviewed · Calculation methodology
Quick Answer
Enter the project dimensions, gravel depth, material type, and extra percentage to estimate the gravel volume in cubic feet and cubic yards, plus an approximate weight in tons. Every result is a planning estimate, so confirm the final quantity with your supplier before ordering.
Project Details
Estimate gravel volume and tons for decorative cover, walkways, driveways, and drainage areas.
Calculation methodology
Area is calculated from your dimensions, depth is converted from inches to feet, and the two are multiplied to get cubic feet. Cubic feet are divided by 27 for cubic yards, and cubic yards are multiplied by an estimated density to get tons. The extra percentage is applied last, and displayed values are rounded to two decimal places.
Limitations
The densities are planning estimates, not measured specifications, and real gravel weight changes with moisture, stone size, and supplier source. The calculator assumes one uniform layer over level ground and does not model compaction ratios, separate base courses, or structural requirements.
Last reviewed .
How the Gravel Calculator Works
The calculator works through the same steps you would follow on paper. Each step is shown below so you can check the numbers or repeat them by hand.
- Area. In rectangle mode, area = length × width. In circle mode, area = π × (diameter ÷ 2)². In custom mode you enter the area in square feet directly, which is useful for irregular shapes you have already measured.
- Depth conversion. Depth is entered in inches and converted to feet: depth in feet = inches ÷ 12. A 4-inch layer is 0.3333 ft.
- Cubic feet. cubic feet = area in square feet × depth in feet.
- Cubic yards. cubic yards = cubic feet ÷ 27, because one cubic yard holds 27 cubic feet.
- Estimated tons. tons = cubic yards × estimated density in tons per cubic yard, taken from the gravel type you select.
- Extra percentage. The volume and weight are multiplied by (1 + extra ÷ 100) to allow for uneven ground, compaction, edges, and measurement variation.
Length and width can be entered in feet or meters. When meters are selected, dimensions are converted to feet before the area is calculated, so the results stay in cubic feet, cubic yards, and tons.
Cubic Yards to Tons by Gravel Type
Gravel volume is the same for every material, but weight is not. The densities below are the same planning values the calculator uses when you pick a gravel type, so the table and the tool always agree.
| Gravel type | Estimated tons per cubic yard | Common use | Planning note |
|---|---|---|---|
| Pea gravel | 1.4 tons | Walkways, patios, play areas, and decorative beds | Rounded stone stays loose, so edging helps keep it in place. |
| Crushed stone | 1.5 tons | Driveways, road bases, and compacted surfaces | Angular stone locks together and settles when compacted. |
| River rock | 1.35 tons | Drainage beds, dry creek beds, and accent areas | Larger stone sizes leave more air space per cubic yard. |
| Decomposed granite | 1.45 tons | Paths, garden trails, and informal seating areas | Fines wash and compact, so weight varies with moisture. |
These are estimated planning values, not measured specifications. Gravel weight varies with moisture, stone size, supplier source, and how much the material has been compacted. If your supplier quotes a different density, use the custom density option in the calculator instead. For a depth-by-area view of the same math, see the gravel coverage chart.
Three Worked Gravel Examples
Each example below is generated with the same calculation used by the calculator, so entering the same inputs will return the same numbers.
Example 1: Gravel for a 12 × 24 ft driveway
A single-car driveway pad using crushed stone at a 4-inch surface depth, with a 10% allowance for settling and edges.
| Step | Calculation |
|---|---|
| Area | 12 ft × 24 ft = 288 sq ft |
| Depth in feet | 4 in ÷ 12 = 0.3333 ft |
| Cubic feet | 288 × 0.3333 = 96 cu ft |
| Cubic yards | 96 ÷ 27 = 3.56 cu yd |
| Estimated tons | 3.56 × 1.5 = 5.33 tons |
| With 10% extra | 3.91 cu yd, about 5.87 tons |
Order about 3.91 cubic yards, or roughly 5.87 tons, at 1.5 tons per cubic yard.
Example 2: Gravel for a 3 × 20 ft walkway
A narrow garden path using pea gravel at a 3-inch depth, with a 10% allowance for edge spill and uneven ground.
| Step | Calculation |
|---|---|
| Area | 3 ft × 20 ft = 60 sq ft |
| Depth in feet | 3 in ÷ 12 = 0.25 ft |
| Cubic feet | 60 × 0.25 = 15 cu ft |
| Cubic yards | 15 ÷ 27 = 0.56 cu yd |
| Estimated tons | 0.56 × 1.4 = 0.78 tons |
| With 10% extra | 0.61 cu yd, about 0.86 tons |
Order about 0.61 cubic yards, or roughly 0.86 tons, at 1.4 tons per cubic yard.
Example 3: Gravel for a 10 × 100 ft road section
A 100-foot stretch of gravel lane using crushed stone at a 4-inch depth, with a 10% allowance for compaction losses.
| Step | Calculation |
|---|---|
| Area | 10 ft × 100 ft = 1000 sq ft |
| Depth in feet | 4 in ÷ 12 = 0.3333 ft |
| Cubic feet | 1000 × 0.3333 = 333.33 cu ft |
| Cubic yards | 333.33 ÷ 27 = 12.35 cu yd |
| Estimated tons | 12.35 × 1.5 = 18.52 tons |
| With 10% extra | 13.58 cu yd, about 20.37 tons |
Order about 13.58 cubic yards, or roughly 20.37 tons, at 1.5 tons per cubic yard.
A longer walk-through of the first two projects is available in the 12×24 driveway example and the 3×20 walkway example.
How to Estimate Gravel for a Road or Driveway
Driveways and gravel lanes carry weight, so the estimate needs a little more care than a decorative bed. The volume math is identical — this page works as a gravel road calculator as well as a landscape one — but the depth and material choices matter more.
- Measure length and width. Include turnarounds, parking aprons, and any widened sections, and measure them separately if the shape is not a simple rectangle.
- Choose a realistic compacted depth. A finished 4-inch surface layer needs more loose material than 4 inches, because gravel settles as it is rolled or driven on.
- Decide whether a base layer is needed. Many driveways use a coarser base course under the surface gravel. If so, estimate each layer separately and add the results.
- Select the gravel type. Angular crushed stone locks together under traffic; rounded stone tends to shift and rut.
- Allow for compaction and uneven ground. Ruts, soft spots, and low areas absorb more material than a flat measurement suggests.
- Confirm the weight conversion. Suppliers deliver by the ton or by the cubic yard, and their density is the one your invoice will use.
Driveway and road base requirements depend on soil, drainage, climate, vehicle weight, and local construction practice. This calculator is for preliminary quantity planning, not structural engineering advice. For depth guidance by project type, see how deep gravel should be.
| Depth | Use | Planning note |
|---|---|---|
| 2 inches | Decorative cover | Best for low-traffic coverage over fabric or firm soil. |
| 3 inches | Walkway | Common for foot traffic with edging to hold the stone. |
| 4+ inches | Driveway or heavier use | Often paired with a separate compacted base course. |
How Much Extra Gravel Should You Order?
Loose material rarely covers exactly what a flat measurement predicts. The allowances below are general planning guidance rather than fixed rules, and the right number depends on how confident you are in your measurements and how level the ground is.
| Extra allowance | Typical fit | Why |
|---|---|---|
| 5% | Simple, regular areas measured accurately | Flat, square sites on firm ground lose very little material. |
| 10% | Most driveways, walkways, and landscape beds | Covers ordinary settling, edge loss, and small measuring differences. |
| 15% | Curved, sloped, or uneven sites | Low spots, slopes, and heavier compaction absorb noticeably more stone. |
Measuring Irregular Areas
Beds and paths are rarely perfect rectangles. Rather than guessing at an average, break the shape down:
- Split the project into smaller rectangles.
- Calculate the square footage of each section separately.
- Add the section areas together for one total.
- For curved sections, use a reasonable approximation — a circle or half-circle for rounded ends, or an average width for a gently curving path.
- Add a suitable extra allowance, usually toward the higher end for irregular shapes.
Once you have the total square footage, switch the calculator above to Custom square feet and enter it directly. The circle mode handles round beds and fire-pit surrounds without any extra math.
Bagged Gravel vs Bulk Delivery
How you buy gravel changes what you need from the estimate. Bagged stone is measured in cubic feet, while bulk stone is usually sold by the ton or the cubic yard.
| Consideration | Bagged gravel | Bulk delivery |
|---|---|---|
| Project size | Small beds, repairs, and touch-ups | Driveways, roads, and larger landscape areas |
| How it is sold | Clear bag volume printed in cubic feet | Usually by the ton or the cubic yard |
| Transport | Easier to move by car and carry by hand | Delivery truck access and a drop location are required |
| Cost per unit | Often higher per cubic foot | Generally lower per unit, but minimum orders may apply |
Supplier density and minimum order quantities vary, so check both before deciding. Prices change by region and season, so compare current quotes rather than relying on published averages.
Common Gravel Calculation Mistakes
- Forgetting to convert inches to feet. Entering a depth of 4 instead of 0.3333 ft overstates the volume by a factor of twelve.
- Confusing square feet with cubic feet. Square feet describe surface area; cubic feet describe the volume once depth is included.
- Confusing cubic yards with tons. One measures space, the other measures weight, and only the density links them.
- Using one density for every gravel type. River rock and crushed stone can differ by more than 10% per cubic yard.
- Ignoring compaction or uneven ground. Gravel settles, and low spots swallow material.
- Measuring only the visible surface. If the project needs a base layer, that volume has to be estimated too.
- Rounding bulk orders down. Coming up short on a delivery usually costs more than the extra material would have.
For a plain-language walk-through of the whole process, read how much gravel do I need or the gravel material guide.
FAQ
How do I calculate cubic yards of gravel?+
Multiply length by width to get the area in square feet, convert the depth from inches to feet by dividing by 12, multiply area by depth to get cubic feet, then divide cubic feet by 27 to get cubic yards.
How many tons are in a cubic yard of gravel?+
Most landscape gravels fall somewhere around 1.3 to 1.5 tons per cubic yard. The planning values used here are 1.4 for pea gravel, 1.5 for crushed stone, 1.35 for river rock, and 1.45 for decomposed granite. Your supplier's quoted density is the number to order against.
How deep should gravel be for a driveway?+
Four inches or more is a common starting point for a driveway surface layer, and many driveways also need a separate compacted base underneath. Soil type, drainage, climate, and vehicle weight change what is appropriate, so check local practice before ordering.
How much extra gravel should I order?+
Around 5% extra suits simple, well-measured rectangles, 10% is a common allowance for typical driveways and walkways, and 15% is reasonable for curved, sloped, or uneven areas where more material settles into low spots.
Can I use this calculator for a gravel road?+
Yes, for volume and weight planning. Measure the road section, enter a realistic compacted depth, and pick the material type. It estimates quantities only and does not replace engineering guidance on road base, subgrade, or load requirements.
Why does gravel weight vary by type?+
Stone shape and size change how much air space sits between the stones, and moisture adds weight. Angular crushed stone packs more tightly than rounded river rock, so the same cubic yard can weigh noticeably more or less.
Should I order gravel by cubic yard or by ton?+
Order in whatever unit your supplier sells in, but calculate the volume first. Cubic yards describe the space you need to fill, and tons describe weight, so the density is what connects the two.