Concrete Cubic Yard Calculator
Estimate order yardage, conversions, and estimated costs in seconds.
Concrete Cubic Yard Calculator: Get Your Exact Yardage in Seconds
When you call a ready-mix supplier to order concrete, there one number they need from you: cubic yards. Not square feet, not bags, not tons—cubic yards. It is the universal ordering unit for ready-mix concrete across the United States, and if you cannot convert your project dimensions into cubic yards accurately, you risk ordering the wrong amount and facing the most preventable and expensive problems in concrete construction.
This concrete cubic yard calculator converts your project dimensions directly into cubic yards, the exact number to quote your supplier. Enter your length, width, and thickness for any shape, and get an instant result in cubic yards with the 10% waste factor already applied. You also get the equivalent in cubic feet, cubic meters, pre-mix bag counts, total weight, and an estimated material cost so you have everything you need in one place before you make a single call.
Whether you are calculating a simple backyard patio, a long driveway, a set of deck footings, or a multi-structure combined pour, this tool gives you the precise cubic yard figure you need to order confidently, avoid short-load fees, and keep your pour on schedule and on budget.
What Is a Cubic Yard of Concrete?
A cubic yard is a unit of volume equal to a cube that measures exactly 3 feet on each side: 3 ft x 3 ft x 3 ft = 27 cubic feet. It is the standard unit used by ready-mix concrete suppliers across the United States for measuring, pricing, and delivering concrete.
Understanding what a cubic yard represents physically helps you verify that your calculations are in the right range before you place an order:
- One cubic yard of concrete fills a space 3 feet long, 3 feet wide, and 3 feet deep
- One cubic yard covers 81 square feet at a 4-inch thickness (a roughly 9 x 9 ft area)
- One cubic yard covers 54 square feet at a 6-inch thickness (a roughly 7.3 x 7.3 ft area)
- One cubic yard weighs approximately 4,050 lbs—about the weight of a compact car
- One cubic yard equals exactly 27 cubic feet or approximately 0.765 cubic meters
- A standard ready-mix truck carries 8 to 10 cubic yards per load
Key fact: There are exactly 27 cubic feet in one cubic yard. This single conversion—dividing cubic feet by 27—is the most important calculation in all concrete work. Every cubic yard calculation begins and ends here.
Why Cubic Yards Are the Standard Ordering Unit
Concrete is measured, priced, and delivered in cubic yards in the US for practical reasons rooted in the industry's production and delivery systems:
- Batch plant production: Ready-mix plants batch concrete in cubic-yard increments. The plant's automated systems weigh and measure cement, aggregate, sand, water, and admixtures per yard of finished concrete. Quoting an order in any other unit requires the plant dispatcher to convert anyway.
- Truck capacity: Standard ready-mix trucks hold 8 to 10 cubic yards. Truck capacity, pour scheduling, and delivery logistics are all planned around yard increments.
- Pricing and contracts: Concrete is priced per cubic yard by every US supplier. Material cost calculations, bid proposals, and purchase orders all use cubic yards as the basis.
- Industry communication: Every concrete professional—contractors, estimators, engineers, and suppliers—communicates in cubic yards. Using the same unit eliminates the miscommunication errors that occur when one party is in cubic feet and another is in cubic meters.
Cubic Yard Formula for Every Concrete Shape
Rectangular Slab, Driveway, Walkway, or Wall
Cubic Yards = (Length ft x Width ft x Thickness ft) / 27
Thickness conversion: inches / 12 = feet | 4 in = 0.333 ft | 5 in = 0.417 ft | 6 in = 0.500 ft | 8 in = 0.667 ft | 12 in = 1.000 ft
Cylinder (Column, Pier, Post Hole, Sonotube)
Cubic Yards = (π x Radius² x Height ft) / 27
Radius = Diameter / 2 (convert diameter from inches to feet first). Example: 12-in diameter = 1.0 ft diameter = 0.5 ft radius.
Multiple Structures Single Combined Order
Total Cubic Yards = Structure A + Structure B + Structure C (+ more)
Final Order = Total Cubic Yards x 1.10 (10% waste factor)
Apply waste factor once to the combined total, not to each structure individually.
Waste Factor Modifier
Order Quantity = Calculated Cubic Yards x Waste Factor
Standard: x 1.10 | Rough terrain: x 1.15 | Complex shapes: x 1.20
Rounding for Supplier Orders
Always round up to the nearest 0.25 cubic yard. Never round down.
Examples: 1.12 yd³ → order 1.25 | 3.42 yd³ → order 3.50 | 7.87 yd³ → order 8.00
How to Calculate Cubic Yards of Concrete: Step by Step
- Measure your project dimensions in feet and inches.
- Convert any thickness measurements from inches to feet by dividing by 12.
- Multiply length x width x thickness (all in feet) to get cubic feet.
- Divide the cubic feet result by 27 to get cubic yards.
- For multiple structures, sum all individual cubic yard volumes first.
- Multiply the total by 1.10 to add a 10% waste factor.
- Round up to the nearest 0.25 cubic yard.
- Quote this final number to your ready-mix supplier.
Real-World Cubic Yard Calculation Examples
Example 1: Backyard Patio 16 x 20 ft, 4 inches thick
| Step | Calculation | Result |
|---|---|---|
| Convert thickness | 4 in / 12 | 0.333 ft |
| Cubic feet | 16 x 20 x 0.333 | 106.56 ft³ |
| Cubic yards (exact) | 106.56 / 27 | 3.95 yd³ |
| Add 10% waste | 3.95 x 1.10 | 4.34 yd³ |
| Round up to order | — | 4.50 yd³ |
| Est. material cost | 4.50 x $150 | ~$675 |
Example 2: Standard Driveway 12 x 45 ft, 5 inches thick
| Step | Calculation | Result |
|---|---|---|
| Convert thickness | 5 in / 12 | 0.417 ft |
| Cubic feet | 12 x 45 x 0.417 | 225.18 ft³ |
| Cubic yards (exact) | 225.18 / 27 | 8.34 yd³ |
| Add 10% waste | 8.34 x 1.10 | 9.17 yd³ |
| Round up to order | — | 9.25 yd³ |
| Est. material cost | 9.25 x $155 | ~$1,434 |
Example 3: Eight Deck Footings 10-inch diameter, 3 ft deep each
| Step | Calculation | Result |
|---|---|---|
| Convert diameter to feet | 10 in / 12 | 0.833 ft |
| Radius | 0.833 / 2 | 0.417 ft |
| Volume per footing | 3.14159 x (0.417)² x 3 | 1.638 ft³ |
| Volume for 8 footings | 1.638 x 8 | 13.10 ft³ |
| Cubic yards | 13.10 / 27 | 0.485 yd³ |
| Add 10% waste | 0.485 x 1.10 | 0.534 yd³ |
| Recommendation | — | Use bags: ~24 x 60 lb bags |
Example 4: Garage Floor + Apron Combined Single Order
| Structure | Dimensions | Cubic Yards |
|---|---|---|
| Garage floor | 20 x 24 ft, 4 in thick | 5.93 yd³ |
| Driveway apron | 12 x 8 ft, 5 in thick | 1.48 yd³ |
| Combined exact total | — | 7.41 yd³ |
| Add 10% waste | — | 8.15 yd³ |
| Round up to order | — | 8.25 yd³ |
| Est. material cost | 8.25 x $158 | ~$1,304 |
Cubic Yard Quick Reference: Most Common Slab Sizes
Pre-calculated cubic yard figures for standard slab dimensions. All values include a 10% waste factor and are rounded up to the nearest 0.25 yard. Use these for quick verification of your calculator results.
4-Inch Thick Slabs
| Slab Size | Exact yd³ | Order Qty (+10%) | 80 lb Bags | Est. Cost @ $150/yd |
|---|---|---|---|---|
| 6 x 6 ft | 0.44 yd³ | 0.50 yd³ | ~27 bags | ~$75 |
| 8 x 8 ft | 0.79 yd³ | 0.75 yd³ | ~40 bags | ~$113 |
| 10 x 10 ft | 1.23 yd³ | 1.25 yd³ | ~62 bags | ~$188 |
| 10 x 16 ft | 1.98 yd³ | 2.00 yd³ | ~99 bags | ~$300 |
| 10 x 20 ft | 2.47 yd³ | 2.75 yd³ | ~122 bags | ~$413 |
| 12 x 12 ft | 1.78 yd³ | 2.00 yd³ | ~88 bags | ~$300 |
| 12 x 16 ft | 2.37 yd³ | 2.50 yd³ | ~118 bags | ~$375 |
| 12 x 20 ft | 2.96 yd³ | 3.25 yd³ | ~148 bags | ~$488 |
| 14 x 20 ft | 3.46 yd³ | 3.75 yd³ | ~172 bags | ~$563 |
| 16 x 16 ft | 3.16 yd³ | 3.50 yd³ | ~157 bags | ~$525 |
| 16 x 20 ft | 3.95 yd³ | 4.25 yd³ | ~196 bags | ~$638 |
| 16 x 24 ft | 4.74 yd³ | 5.25 yd³ | ~236 bags | ~$788 |
| 20 x 20 ft | 4.94 yd³ | 5.50 yd³ | ~245 bags | ~$825 |
| 20 x 24 ft | 5.93 yd³ | 6.50 yd³ | ~294 bags | ~$975 |
| 20 x 30 ft | 7.41 yd³ | 8.25 yd³ | ~367 bags | ~$1,238 |
| 24 x 24 ft | 7.11 yd³ | 8.00 yd³ | ~352 bags | ~$1,200 |
| 24 x 30 ft | 8.89 yd³ | 10.00 yd³ | ~440 bags | ~$1,500 |
| 24 x 40 ft | 11.85 yd³ | 13.00 yd³ | ~587 bags | ~$1,950 |
| 30 x 30 ft | 11.11 yd³ | 12.25 yd³ | ~550 bags | ~$1,838 |
| 30 x 40 ft | 14.81 yd³ | 16.25 yd³ | ~734 bags | ~$2,438 |
5-Inch Thick Slabs
| Slab Size | Exact yd³ | Order Qty (+10%) | 80 lb Bags | Est. Cost @ $155/yd |
|---|---|---|---|---|
| 10 x 20 ft | 3.09 yd³ | 3.25 yd³ | ~153 bags | ~$504 |
| 12 x 40 ft | 7.41 yd³ | 8.25 yd³ | ~367 bags | ~$1,279 |
| 16 x 20 ft | 4.94 yd³ | 5.50 yd³ | ~245 bags | ~$853 |
| 20 x 20 ft | 6.17 yd³ | 6.75 yd³ | ~306 bags | ~$1,046 |
| 20 x 40 ft | 12.35 yd³ | 13.50 yd³ | ~612 bags | ~$2,093 |
| 24 x 40 ft | 14.81 yd³ | 16.25 yd³ | ~734 bags | ~$2,519 |
6-Inch Thick Slabs
| Slab Size | Exact yd³ | Order Qty (+10%) | 80 lb Bags | Est. Cost @ $158/yd |
|---|---|---|---|---|
| 10 x 10 ft | 1.85 yd³ | 2.00 yd³ | ~92 bags | ~$316 |
| 12 x 20 ft | 4.44 yd³ | 5.00 yd³ | ~220 bags | ~$790 |
| 16 x 20 ft | 5.93 yd³ | 6.50 yd³ | ~293 bags | ~$1,027 |
| 20 x 20 ft | 7.41 yd³ | 8.25 yd³ | ~367 bags | ~$1,304 |
| 20 x 40 ft | 14.81 yd³ | 16.25 yd³ | ~734 bags | ~$2,568 |
| 24 x 40 ft | 17.78 yd³ | 19.50 yd³ | ~880 bags | ~$3,081 |
| 30 x 40 ft | 22.22 yd³ | 24.50 yd³ | ~1,100 bags | ~$3,871 |
| 40 x 60 ft | 44.44 yd³ | 49.00 yd³ | — ready-mix only | ~$7,742 |
Cylinders Cubic Yards per Single Column or Post Hole
| Diameter | 1 ft Deep | 2 ft Deep | 3 ft Deep | 4 ft Deep | 6 ft Deep |
|---|---|---|---|---|---|
| 6 in | 0.01 yd³ | 0.02 yd³ | 0.03 yd³ | 0.04 yd³ | 0.07 yd³ |
| 8 in | 0.02 yd³ | 0.03 yd³ | 0.05 yd³ | 0.07 yd³ | 0.10 yd³ |
| 10 in | 0.02 yd³ | 0.05 yd³ | 0.07 yd³ | 0.09 yd³ | 0.14 yd³ |
| 12 in | 0.04 yd³ | 0.07 yd³ | 0.11 yd³ | 0.14 yd³ | 0.21 yd³ |
| 14 in | 0.05 yd³ | 0.10 yd³ | 0.15 yd³ | 0.19 yd³ | 0.29 yd³ |
| 16 in | 0.06 yd³ | 0.13 yd³ | 0.20 yd³ | 0.26 yd³ | 0.39 yd³ |
| 18 in | 0.08 yd³ | 0.16 yd³ | 0.24 yd³ | 0.33 yd³ | 0.49 yd³ |
| 24 in | 0.15 yd³ | 0.29 yd³ | 0.44 yd³ | 0.58 yd³ | 0.87 yd³ |
Cubic Yards to Bags Conversion
When your project falls below the ready-mix threshold (approximately 1 cubic yard), pre-mix bags become the more practical choice. Use this conversion to determine which bag size and quantity to buy.
| Cubic Yards Needed | 40 lb Bags (0.30 ft³ each) | 60 lb Bags (0.45 ft³ each) | 80 lb Bags (0.60 ft³ each) |
|---|---|---|---|
| 0.10 yd³ (2.7 ft³) | 9 bags | 6 bags | 5 bags |
| 0.25 yd³ (6.75 ft³) | 23 bags | 15 bags | 12 bags |
| 0.50 yd³ (13.5 ft³) | 45 bags | 30 bags | 23 bags |
| 0.75 yd³ (20.25 ft³) | 68 bags | 45 bags | 34 bags |
| 1.00 yd³ (27 ft³) | 90 bags | 60 bags | 45 bags |
| 1.25 yd³ (33.75 ft³) | 113 bags | 75 bags | 57 bags |
| 1.50 yd³ (40.5 ft³) | 135 bags | 90 bags | 68 bags |
| 2.00 yd³ (54 ft³) | 180 bags | 120 bags | 90 bags |
Cubic Yards to Cost: Ready-Mix Price Reference
| Cubic Yards | 3,000 PSI ($148/yd) | 3,500 PSI ($163/yd) | 4,000 PSI ($178/yd) |
|---|---|---|---|
| 1 yd³ | $148 | $163 | $178 |
| 2 yd³ | $296 | $326 | $356 |
| 3 yd³ | $444 | $489 | $534 |
| 5 yd³ | $740 | $815 | $890 |
| 7 yd³ | $1,036 | $1,141 | $1,246 |
| 10 yd³ | $1,480 | $1,630 | $1,780 |
| 15 yd³ | $2,220 | $2,445 | $2,670 |
| 20 yd³ | $2,960 | $3,260 | $3,560 |
| 30 yd³ | $4,440 | $4,890 | $534 |
| 50 yd³ | $7,400 | $8,150 | $8,900 |
Price note: These are material-only costs at mid-range 2025 US prices. Add delivery fee ($0 to $150), labor ($3.50 to $7.00 per sq ft), subbase, reinforcement, and finishing for total project cost. Regional prices vary significantly—always get local quotes before finalizing your budget.
Cubic Yard Waste Factor Guide
| Project Type | Recommended Waste | Multiplier | Reason |
|---|---|---|---|
| Commercial slab, laser-leveled, steel forms | 5% | x 1.05 | Precision prep minimizes all loss sources |
| Standard residential slab or driveway | 10% | x 1.10 | Industry standard — most homeowner projects |
| Uneven subgrade, rough terrain | 15% | x 1.15 | Low spots and base variation consume extra concrete |
| First-time DIY pour | 15% | x 1.15 | Measurement error and form gaps increase usage |
| Complex or irregular shapes | 20% | x 1.20 | Multiple transitions and curved edges add waste |
| Multi-structure combined order | 10% | x 1.10 | Apply once to combined total, not per structure |
How Many Cubic Yards in a Concrete Truck?
Understanding truck capacity is critical for planning large pours and managing delivery scheduling.
| Truck Type | Min. Load | Typical Load | Max Load | Best Application |
|---|---|---|---|---|
| Mini mixer (short load) | 0.5 yd³ | 2–3 yd³ | 4 yd³ | Small residential pours, tight access |
| Standard rear-discharge mixer | 1 yd³ | 8–9 yd³ | 10 yd³ | Most residential and light commercial |
| Front-discharge mixer | 1 yd³ | 9–10 yd³ | 11 yd³ | Larger residential and commercial pours |
| Volumetric mixer | 0.25 yd³ | Variable | Unlimited | Remote sites, precise quantities, specialty mixes |
Cubic Yard Ordering Checklist
- Calculated exact cubic yards using the correct formula for each structure
- Applied waste factor (10% standard, 15% for rough terrain)
- Rounded up to the nearest 0.25 cubic yard
- Confirmed the mix strength required (3,000 PSI, 3,500 PSI, 4,000 PSI)
- Checked supplier's minimum delivery quantity and short-load fee policy
- Verified truck access to the pour location (width, clearance, ground bearing)
- Scheduled pour day crew and tools before calling supplier
- Confirmed delivery window with at least 24 hours notice
- Have curing compound on-site for immediate post-pour application
Common Cubic Yard Calculation Mistakes
- Not converting thickness from inches to feet: 4 inches used as 4 feet inflates the cubic yard result by 12 times. A 20x20 slab at 4 inches thick needs 4.94 yards. The same calculation with 4 feet produces 59.3 yards—a 12-truck error. Always divide inches by 12 before multiplying.
- Forgetting to divide by 27: Cubic feet are not cubic yards. Stopping the calculation at cubic feet and calling that number your yard order results in an order 27 times larger than you need. Always complete the division.
- Rounding down instead of up: Rounding 3.42 yards down to 3.25 or 3.0 guarantees a short pour. Always round up to the next 0.25 increment. The cost of an extra quarter yard is $35 to $50. The cost of running short is a cold joint.
- Not checking the short-load threshold: An order of 2.8 yards when your supplier's short-load minimum is 3 yards means paying a $75 to $150 surcharge anyway. Round your order up to the threshold and avoid the fee.
- Applying waste factor to each structure separately in a multi-pour: Calculating three structures at 1.10 waste each and then adding them produces a higher total than calculating the exact sum first and applying 1.10 once. The difference is small but adds up on large multi-structure projects.
- Confusing linear yards with cubic yards: A yard of fabric and a yard of concrete are completely different. Concrete is always ordered in cubic yards (volume). There is no linear yard of concrete. This confusion occasionally causes homeowners to order 27 times less concrete than they need.
Pro Tips for Cubic Yard Ordering
- Always quote your supplier in quarter-yard increments: Suppliers batch in 0.25-yard steps. If your number is 4.34 yards, say 4.50. If it is 7.12, say 7.25. This is the language of the industry.
- For large pours over 8 yards, call your supplier the day before to confirm your order, truck size, and delivery window: Last-minute large orders sometimes cannot be filled at peak season. A pre-confirmation call locks your slot.
- Know your site's access constraints before ordering: A full-size mixer needs at least 10 feet of clearance width and firm ground. If your site has trees, fences, or soft soil, discuss mini-mixer or pump options with your supplier before pour day.
- For projects right at the short-load threshold, ask your supplier about their mini-mixer option: Many suppliers offer smaller trucks for residential jobs that reduce the short-load fee significantly.
- Calculate your cubic yards, then do a sanity check with the quick reference table: If the table shows 4.35 yards for a 16x20 slab at 4 inches and your calculation shows 14.35 yards, you have a unit error. The table catches mistakes before they become expensive orders.
- Keep a copy of your cubic yard calculation with the project file: If a dispute arises about whether the correct amount was ordered or delivered, your documented calculation is the reference.