Quick Answer: A cubic yard calculator uses the mathematical terms of length x width x depth (in feet), then divides it by 27. The things that people manufacture in bulk such as concrete, gravel, soil, and mulch are priced by the cubic yard; with this information you can order the right amount so you are not left ordering more than you actually need or ordering less in the middle of a project.
When ordering materials in bulk for a driveway, patio or garden, you might find you’re asked at supplier’s counter how many yards you need, and if you’ve never measured a space before in yards and want to know the formula for calculating any other area, you probably need to keep your distance from the counter. Ordering too little means that you will incur the cost of the second delivery charge, ordering too much means that you end up spending time and money to dispose of the excess concrete/gravel.
Every cubic yard calculator formula for you, from feet and inches, examples of actual projects and numbers that do the work, and what delivery size of truck capacities and waste sections to use you will find the exact answer here.
What Is a Cubic Yard?
A cubic yard (written as yd³ or cu yd) is a unit of volume equal to the space inside a cube measuring exactly one yard, or three feet, on every side. It’s the standard unit suppliers use for pricing and delivering bulk landscaping and construction materials in the United States, including concrete, topsoil, mulch, sand, and crushed gravel.
As documented on Wikipedia’s entry for the cubic yard, the unit is part of the imperial and US customary measurement systems and converts to exactly 0.764554857984 cubic meters. One cubic yard equals 27 cubic feet, since a yard is 3 feet and 3 × 3 × 3 = 27.
Quick Fact: A single cubic yard of material weighs anywhere from about 2,000 pounds (loose mulch) to over 4,000 pounds (wet sand or gravel), which is why suppliers price and deliver by volume rather than by weight for most landscaping materials.
Using a Cubic Yard Calculator: The Basic Formula
Every cubic yard calculator runs on the same underlying formula:
Cubic Yards = (Length ft × Width ft × Depth ft) ÷ 27
The steps:
- Measure the length and width of the area in feet.
- Determine the depth or thickness of material you need — often given in inches — and convert it to feet.
- Multiply length × width × depth to get the volume in cubic feet.
- Divide that number by 27 to convert to cubic yards.
The division by 27 is the step people forget, since it’s easy to calculate cubic feet correctly and then order that number in yards by mistake — a rectangular error that can leave a job dramatically short on material.
Converting Feet to Cubic Yards
If all of the measurements are already given in feet, the conversion step comes after the step for volume. In feet, length × width × depth results in cubic feet (cft) which can be divided by 27 to get back the number of cubic inches.
Example: A garden bed measuring 10 ft × 6 ft with 1.5 ft of soil depth: 10 × 6 × 1.5 = 90 cubic feet. Divide the number 27 for the 3.33 yd of soil required.
Converting Inches to Cubic Yards
Generally, depth will be provided in inches (a 4 inch concrete slab), length and width will be in feet, and dimension is specified only once it reaches the eyes. To calculate depth in feet first: divide the inch value by 12 and then use the standard formula.
A shortcut doesn’t go through the two-step conversion
you divide length (ft) × width (ft) × depth (inches) by 324, rather than 27.
The 324 divisor is a combination of both (12 x 27 = 324 – 12 inches to feet, then 27 x feet to cubic yards (12 x 27 = 324).
Cubic Yards = (Length ft × Width ft × Depth inches) ÷ 324
Converting Depth in Inches: The Trick Landscapers Use
Suppliers and landscapers often recommend standard depths depending on the material: 2–3 inches for mulch, 4 inches for a gravel base, 4–6 inches for a concrete slab, and 6–8 inches for a driveway sub-base. Rather than re-measuring for every project, keeping this depth-to-coverage relationship in mind speeds up estimating:
| Depth | Coverage per Cubic Yard |
| 1 inch | 324 sq ft |
| 2 inches | 162 sq ft |
| 3 inches | 108 sq ft |
| 4 inches | 81 sq ft |
| 6 inches | 54 sq ft |
This table works in reverse too — if you know the area you’re covering, divide 324 by the depth in inches to find how many square feet one cubic yard covers at that thickness.
Worked Example: Concrete Slab or Patio
Scenario: A backyard patio slab measures 20 feet by 20 feet, poured 4 inches thick.
| Step | Calculation | Result |
| Length × Width | 20 ft × 20 ft | 400 ft² |
| Depth in feet | 4 in ÷ 12 | 0.333 ft |
| Volume in cubic feet | 400 ft² × 0.333 ft | 133.3 ft³ |
| Convert to cubic yards | 133.3 ÷ 27 | 4.94 yd³ |
The slab needs roughly 4.94 cubic yards of concrete. Since concrete suppliers typically sell in quarter- or half-yard increments and running short mid-pour isn’t an option, most contractors round up to 5 or 5.25 cubic yards and add a small buffer on top of that.
Worked Example: Gravel Driveway
Scenario: A gravel driveway measures 60 feet long by 12 feet wide, with a 6-inch base layer.
- 60 ft × 12 ft = 720 ft²
- 6 in ÷ 12 = 0.5 ft
- 720 ft² × 0.5 ft = 360 ft³
- 360 ÷ 27 = 13.33 cubic yards of gravel
A load this size typically requires a standard dump truck delivery rather than a pickup-truck run, which matters when scheduling a supplier drop-off. If the driveway surface itself is asphalt rather than gravel, the Asphalt Calculator handles that material’s own thickness and tonnage math separately.
Worked Example: Circular or Curved Garden Bed
Round garden beds and tree rings need a different formula since they aren’t rectangular:
Cubic Yards = (π × radius² × depth ft) ÷ 27
Scenario: A circular flower bed with a 5-foot radius, filled 6 inches deep.
- π × 5² = 78.54 ft²
- 6 in ÷ 12 = 0.5 ft
- 78.54 × 0.5 = 39.27 ft³
- 39.27 ÷ 27 = 1.45 cubic yards of soil or compost
Cubic Yards vs. Cubic Feet vs. Cubic Meters
Different suppliers and industries default to different units depending on region and material type:
| Unit | Equal To | Commonly Used For |
| 1 cubic yard | 27 cubic feet | Concrete, soil, gravel, mulch delivery |
| 1 cubic foot | 1/27 cubic yard | Appliances, small containers, bagged material |
| 1 cubic meter | 1.31 cubic yards | International or metric-region suppliers |
Bagged materials from a hardware store are usually labeled in cubic feet, while bulk delivery orders are priced in cubic yards — knowing both units matters when comparing a bag-by-bag purchase against a bulk delivery for the same project.
How Much Does a Dump Truck or Delivery Load Hold?
After determining your project’s cubic yardage, you will be able to compare that cubic yardage with average delivery amounts so you can determine the number of loads you’ll need for your project:
The majority of pick-up trucks come with a standard capacity of one-two cubic yards, the specifics of which vary as a function of the material being loaded into the bed.
There are 5-7 cubic yards in a dump truck with one axle and a small capacity.
The most common trucks for delivering landscape material are standard tandem dump trucks, which can carry 10-14 cubic yards of material per truck.
If you have a patio requiring 4.94 cubic yards, one load in the pickup at this size would not be sufficient; however, it would fit in a small dump truck.
Common Materials Measured in Cubic Yards
These are all delivered and sold by the cubic yard:
Concrete — Slabs, footings, sidewalks and foundations.
For garden beds, lawns and raised planters: Topsoil and/or compost.
Mulch — Wood chips or bark (for landscaping beds) or rubber mulch.
Gravel and crushed stone – in driveways, drainage and sub-base layer.
Drainage projects, Playgrounds & Paver bases, use Sand.
The volume will be the same for all, but the cost and delivery weight limit will be different for each.
Why Suppliers Sell by the Cubic Yard Instead of Cubic Feet
The cubic yard unit is useful for bulk delivery pricing because the unit of scale with the truck capacity is clean with a load of 10-14 cubic yards rather than a number in the hundreds of cubic feet. Besides, it’s mor Edmonton’s Resources simply less exclusive and less prone to mistakes when used on a large scale: ordering “5 yards of concrete” is a purer discussion with a suppliers than ordering “135 cubic feet,” as each term refers to an identical volume of concrete.
Calculating Cubic Yards for Irregular or Multi-Section Areas
Real driveways, patios and garden beds do not form perfect rectangles. If the patio is L-shaped, break it down into two rectangles, compute the cubic yardage of each one individually and add the quantities together. If the bed is curved, measure the widest width, the narrowest width and the width in the middle, and average those three widths then use the standard formula by using average width.
How Much Extra to Order: The Waste and Settling Buffer
Despite precise calculations, it is difficult to exactly replicate what is used on site. There is a little bit of variance between the measurements as there’s an imbalance in the ground, compaction, spillage as it’s being placed, and minor variance in the actual measurements. It is standard practice across all concrete, gravel, soil suppliers to add about 5–10% more to what is finalized on the computer so there is no chance of a shortage at mid-pour.
Common Mistakes When Calculating Cubic Yardage
There are a few common mistakes made when calculating cube yards:
- Not knowing how to compute the cubic feet, and then ordering that number of yards.
- Move in inches (Use inches with length x width x depth without change to convert length x width in feet to inches) — Move in inches, multiply length x width (in feet) x depth (in inches) without converting length x width to inches.
- Without a waste buffer ordering the precise quantity calculated, and running short after the waste has been considered, along with spillage.
- Getting an “average” depth on sloping or uneven ground assuming that a single depth represents an excavation or fill depth for all areas on slopes or uneven ground.
Frequently Asked Questions
What is the volume of a yard cube? A yard has 3 feet in length times 3 in breadth times 3 in height and 27 x 27 x 27 = 27 cubic yards.
What is the amount of cubic yards needed for concrete? Multiply the length (in feet) x the width (in feet) x the depth (in feet), then divide by 27. Instead, divide length x width x depth (in.) by 324 for depth in inches.
How much should I add for waste when ordering bulk material? Most suppliers recommend adding 5–10% on top of your calculated volume to account for compaction, spillage, and measurement variance.
Can I use square footage to estimate cubic yards? Yes — multiply the area in square feet by the depth in feet to get cubic feet, then divide by 27. This shortcut works whenever you already know the floor or ground area and just need to apply a depth; the Square Foot Calculator is useful for getting that starting area figure first.
Use Techwole’s Cubic Yard-Related Tools
Running the math by hand works for a single quick estimate, but comparing depths, materials, or multiple sections of a project is faster with a dedicated tool. Beyond the formulas covered in this guide, you can explore more free tools on Techwole for the wider set of construction and material-estimating calculators you’re likely to need for the same project — plug in your measurements and skip the manual conversion entirely.