Cubic Yards From Feet Calculator
Enter your length, width, and depth to convert cubic feet into cubic yards. This calculator is ideal for gravel, mulch, topsoil, concrete base, fill dirt, compost, and other landscaping or construction materials.
Project length in feet.
Project width in feet.
Enter depth as a number.
Most landscape projects use inches.
Helpful when ordering bulk material.
Choose how precise the result should appear.
Your results will appear here
Tip: cubic yards = cubic feet ÷ 27. If your depth is in inches, divide by 12 first to convert it to feet.
Volume Visualization
The chart compares your raw cubic feet, equivalent cubic yards, and suggested order quantity after adding your selected allowance.
How to Calculate Cubic Yards From Feet
Calculating cubic yards from feet is one of the most useful skills in landscaping, excavation, hardscaping, and light construction. Whether you are ordering topsoil for a lawn renovation, gravel for a driveway, mulch for flower beds, or sand for a paver base, suppliers commonly sell loose material by the cubic yard. Homeowners, contractors, and property managers often measure a project area in feet, but pricing and delivery are quoted in yards. That is why understanding the conversion matters: it helps you order enough material without paying for excessive overage or risking a costly shortfall.
The core idea is straightforward. A cubic yard is a unit of volume, just like a cubic foot. Since one yard equals three feet, a cubic yard is a space measuring 3 feet by 3 feet by 3 feet. Multiply those dimensions and you get 27 cubic feet in 1 cubic yard. That single relationship drives nearly every practical conversion. Once you know the total cubic feet for your project, you divide by 27 to find cubic yards.
Quick formula: cubic yards = length in feet × width in feet × depth in feet ÷ 27.
If depth is in inches: cubic yards = length in feet × width in feet × depth in inches ÷ 324, because 27 × 12 = 324.
The Basic Formula Explained
Most rectangular projects use three measurements: length, width, and depth. Multiply all three to get cubic feet. Then divide that result by 27. For example, imagine a garden bed that is 18 feet long, 10 feet wide, and 3 inches deep. Because the depth is in inches, convert it to feet first. Three inches is 3 ÷ 12 = 0.25 feet. Then calculate volume:
- 18 × 10 × 0.25 = 45 cubic feet
- 45 ÷ 27 = 1.67 cubic yards
In practice, you would likely order around 1.75 to 2.0 cubic yards depending on the supplier, your tolerance for waste, and whether the material settles or compacts. This is why many professionals add 5% to 15% when placing an order. The allowance accounts for spillage, uneven grading, compaction, and the natural variation of bulk material.
Why the Feet to Yard Conversion Matters
Volume mistakes are surprisingly common. A project can look simple on paper, but even a small misread of depth can dramatically change your order quantity. For instance, confusing 4 inches with 4 feet creates a twelvefold error. Likewise, forgetting to divide cubic feet by 27 can cause someone to overestimate the needed volume. Since delivered aggregate, soil blends, and mulch often involve trucking costs, loader fees, and minimum order thresholds, an inaccurate calculation affects more than just material quantity. It can impact budget, labor efficiency, and schedule.
Accurate conversions also help you compare pricing between suppliers. One company might quote per cubic yard delivered, while another lists a per-ton rate for the same material. If you know your approximate yardage first, you can start narrowing down delivery loads and overall cost much more confidently.
Step-by-Step Method for Real Projects
1. Measure Length and Width in Feet
Use a tape measure, measuring wheel, or site plan. For rectangular spaces, this is easy. For irregular areas, break the site into smaller rectangles, calculate each section separately, and then add the totals together.
2. Measure Depth Carefully
Depth is the most frequently misunderstood measurement. Mulch is often installed at 2 to 4 inches. Gravel for pathways may be 2 to 3 inches. Topsoil might be spread 3 to 6 inches. Paver base or fill layers can be deeper. Always confirm the installed depth you want, not just the material you see in a sample pile.
3. Convert Depth to Feet if Needed
If the depth is in inches, divide by 12. This is essential because the length and width are already in feet. All dimensions must use the same unit before you multiply them.
4. Compute Cubic Feet
Multiply length × width × depth in feet. This gives the total cubic feet of your project.
5. Convert Cubic Feet to Cubic Yards
Divide cubic feet by 27. That gives the raw yardage before waste or compaction adjustments.
6. Add a Practical Ordering Allowance
For many loose materials, 5% to 10% is common. If your project involves uneven terrain, settling, or significant grading loss, 10% to 15% may be safer.
Common Shortcut Formula With Inches
Because many homeowners measure depth in inches, this shortcut saves time:
Cubic yards = length in feet × width in feet × depth in inches ÷ 324
Example: A play area is 24 feet by 16 feet with 4 inches of engineered wood fiber.
- 24 × 16 × 4 = 1,536
- 1,536 ÷ 324 = 4.74 cubic yards
With a 10% allowance, the order would be about 5.21 cubic yards, typically rounded based on supplier increments.
Comparison Table: Common Depths and Coverage
| Coverage Area | Depth | Cubic Feet Needed | Cubic Yards Needed |
|---|---|---|---|
| 100 sq ft | 2 inches | 16.67 cu ft | 0.62 cu yd |
| 100 sq ft | 3 inches | 25.00 cu ft | 0.93 cu yd |
| 100 sq ft | 4 inches | 33.33 cu ft | 1.23 cu yd |
| 200 sq ft | 3 inches | 50.00 cu ft | 1.85 cu yd |
| 300 sq ft | 4 inches | 100.00 cu ft | 3.70 cu yd |
| 500 sq ft | 6 inches | 250.00 cu ft | 9.26 cu yd |
These values are especially useful because they reveal how quickly volume grows with area and depth. A small increase in depth can significantly increase the number of cubic yards needed, which is why careful planning matters.
Typical Bulk Material Densities and Ordering Considerations
Volume tells you how much space material occupies, while weight tells you whether your trailer, truck, or site access can handle the load. Weight per cubic yard varies by moisture content, particle size, and compaction. The table below lists typical planning ranges used in the field. Actual supplier values can differ, but these figures help illustrate why cubic yards are usually the starting point for ordering, and weight becomes the second check.
| Material | Typical Weight per Cubic Yard | Common Installation Depth | Planning Note |
|---|---|---|---|
| Shredded mulch | 400 to 800 lb | 2 to 4 inches | Lightweight, but settles over time. |
| Topsoil | 2,000 to 2,700 lb | 3 to 6 inches | Moisture can change weight significantly. |
| Sand | 2,400 to 3,000 lb | 1 to 4 inches | Often used for bedding and leveling. |
| Gravel | 2,400 to 3,000 lb | 2 to 6 inches | Compaction may reduce apparent volume. |
| Concrete debris / dense fill | 3,000 lb or more | Project-specific | Check haul limits before pickup. |
Examples by Project Type
Mulch Bed Example
A bed measures 30 feet by 8 feet and needs 3 inches of mulch. Use the shortcut formula: 30 × 8 × 3 ÷ 324 = 2.22 cubic yards. If you add a 10% cushion, order about 2.44 cubic yards.
Gravel Driveway Example
A driveway section is 40 feet long, 12 feet wide, and 4 inches deep. The calculation is 40 × 12 × 4 ÷ 324 = 5.93 cubic yards. With a 10% allowance, the recommendation becomes about 6.52 cubic yards.
Topsoil Lawn Repair Example
A lawn patch is 25 feet by 20 feet with 2 inches of topsoil. The volume is 25 × 20 × 2 ÷ 324 = 3.09 cubic yards. If the area is uneven, a 10% to 15% overage may be reasonable.
Mistakes to Avoid
- Mixing units: Do not multiply feet by inches without converting first.
- Ignoring compaction: Gravel, crusher run, and soil can settle after placement.
- Ordering exact theoretical volume: Real sites are rarely perfect rectangles with perfectly flat subgrades.
- Skipping delivery constraints: Access, truck size, and unloading location matter.
- Forgetting material behavior: Wet soil weighs much more than dry mulch.
Authoritative References for Unit Conversions and Material Planning
For unit fundamentals, measurement standards, and practical planning information, these sources are helpful:
- National Institute of Standards and Technology (NIST) for reliable measurement and unit conversion guidance.
- University of Maryland Extension for practical guidance on mulch depth and application.
- Penn State Extension for soil-related planning concepts that influence volume needs and site preparation.
When to Round Up
Bulk material is rarely installed with laboratory precision. If your result is 2.03 cubic yards, many buyers round up to 2.25 or 2.5 depending on supplier increments. For very small projects, bagged product may be more practical. For larger jobs, rounding up can prevent a second delivery charge. A good rule is to round conservatively when labor and delivery are expensive, but avoid excessive over-ordering if storage space or disposal is limited.
Final Takeaway
To calculate cubic yards from feet, first determine cubic feet by multiplying length, width, and depth in feet. Then divide by 27. If your depth is in inches, either convert inches to feet or use the shortcut formula dividing by 324. Add a reasonable allowance for waste and compaction, then round based on supplier availability. This simple process helps you order more accurately, compare supplier pricing, and complete your project with fewer delays.
Use the calculator above whenever you need a quick, reliable estimate. It handles the core conversion, applies your selected waste factor, and visualizes the results so you can make a smarter ordering decision.