Concrete Volume Calculator: Calculate Yards, Feet & Meters for Your Project (Free Tool)
You are pouring a concrete slab for a patio. You need to order concrete. But how much? Too little, and you run out mid-pour. Too much, and you waste money.
Concrete volume is measured in cubic yards (US) or cubic meters (metric). Getting it right saves money and hassle.
Today, I give you a free Concrete Volume Calculator.
You enter length, width, and thickness. The calculator shows:
- Cubic yards
- Cubic feet
- Cubic meters
- Number of concrete bags
Let me explain how to calculate concrete volume.
What is Concrete Volume? (Simple Explanation)
Concrete volume is the amount of space your concrete project occupies. It is measured in cubic units.
Common units:
- Cubic yards (yd³) – US standard for ordering concrete
- Cubic feet (ft³) – Used for bag calculations
- Cubic meters (m³) – Metric standard
The formula:
Volume = Length × Width × Thickness
Example: A 10 ft × 10 ft slab, 4 inches thick
Volume in cubic feet = 10 × 10 × (4 ÷ 12) = 33.33 ft³
Volume in cubic yards = 33.33 ÷ 27 = 1.23 yd³
Why This Concrete Volume Calculator Matters
Here is why you need to calculate concrete volume correctly.
Reason 1: Order the right amount
Concrete is expensive. Ordering too much wastes money. Ordering too little delays your project.
Reason 2: Estimate cost
Concrete costs per cubic yard (US) or cubic meter. Calculate volume to get an accurate quote.
Reason 3: Plan for waste
Add 5-10% extra for spillage, uneven ground, and formwork gaps.
Reason 4: Calculate bagged concrete
If you are mixing your own, you need to know how many 40lb, 60lb, or 80lb bags to buy.
Reason 5: Compare suppliers
Different suppliers quote in different units. Convert to compare prices.
The Concrete Volume Formula
For rectangular slabs:
Volume (yd³) = (Length (ft) × Width (ft) × Thickness (in)) ÷ 324
Volume (ft³) = Length (ft) × Width (ft) × (Thickness (in) ÷ 12)
Volume (m³) = Length (m) × Width (m) × Thickness (m)
For circular slabs:
Volume (yd³) = (π × Radius² × Thickness) ÷ 324
For footings:
Volume = Length × Width × Depth
For walls:
Volume = Length × Height × Thickness
LIVE Concrete Volume Calculator
Enter your dimensions. The calculator shows concrete volume instantly.
🏗️ Concrete Volume Calculator
📏 Shape
📏 Length (ft)
📏 Width (ft)
📏 Thickness (in)
📦 Waste Factor (%)
🏗️ Concrete Volume Calculator
Calculate cubic yards, feet, and meters for slabs, footings, and walls
📏 Shape
Rectangle / Square Circle
📏 Length (ft)
📏 Width (ft)
📏 Radius (ft)
📏 Thickness (in)
📦 Waste Factor (%)
📦 CONCRETE VOLUME
0.00 yd³
0.00 ft³
0.00 m³
0%
💡 Add 5-10% waste for spillage and uneven ground.
🧱 1 cubic yard = 27 cubic feet. A 10’×10′ slab at 4″ thick = 1.23 cubic yards.
How to Use This Concrete Volume Calculator
Follow these 5 simple steps.
Step 1: Select the shape (rectangle or circle)
Step 2: Enter length and width (for rectangle) or radius (for circle)
Step 3: Enter thickness in inches
Step 4: Enter waste factor (5-10% recommended)
Step 5: Read the results in cubic yards, cubic feet, and cubic meters
Real Examples: Different Scenarios
Example 1: Patio slab
- Shape: Rectangle
- Length: 12 ft, Width: 10 ft
- Thickness: 4 inches
- Waste: 10%
Result: 1.48 cubic yards (about 1.5 yards)
Example 2: Circular pad
- Shape: Circle
- Radius: 5 ft
- Thickness: 6 inches
- Waste: 5%
Result: 1.48 cubic yards
Example 3: Driveway
- Shape: Rectangle
- Length: 40 ft, Width: 10 ft
- Thickness: 5 inches
- Waste: 10%
Result: 6.8 cubic yards
Example 4: Sidewalk
- Shape: Rectangle
- Length: 30 ft, Width: 3 ft
- Thickness: 4 inches
- Waste: 10%
Result: 1.22 cubic yards
Concrete Volume by Slab Size (4 inches thick, no waste)
| Slab Size (ft) | Area (sq ft) | Cubic Feet | Cubic Yards |
|---|---|---|---|
| 8×8 | 64 | 21.3 | 0.79 |
| 10×10 | 100 | 33.3 | 1.23 |
| 10×12 | 120 | 40.0 | 1.48 |
| 10×20 | 200 | 66.7 | 2.47 |
| 12×12 | 144 | 48.0 | 1.78 |
| 12×20 | 240 | 80.0 | 2.96 |
| 20×20 | 400 | 133.3 | 4.94 |
| 20×30 | 600 | 200.0 | 7.41 |
| 30×30 | 900 | 300.0 | 11.11 |
| 40×40 | 1,600 | 533.3 | 19.75 |
Concrete Volume by Thickness (10×10 slab)
| Thickness (in) | Cubic Feet | Cubic Yards |
|---|---|---|
| 3 | 25 | 0.93 |
| 4 | 33.3 | 1.23 |
| 5 | 41.7 | 1.54 |
| 6 | 50 | 1.85 |
| 8 | 66.7 | 2.47 |
| 10 | 83.3 | 3.09 |
| 12 | 100 | 3.70 |
Bagged Concrete Calculator
Concrete bags come in different sizes:
| Bag Size | Cubic Feet per Bag | Bags per Cubic Yard |
|---|---|---|
| 40 lb | 0.3 ft³ | 90 |
| 60 lb | 0.45 ft³ | 60 |
| 80 lb | 0.6 ft³ | 45 |
Example: A 10’×10’×4″ slab is 33.3 ft³.
- 40 lb bags: 33.3 ÷ 0.3 = 111 bags
- 60 lb bags: 33.3 ÷ 0.45 = 74 bags
- 80 lb bags: 33.3 ÷ 0.6 = 56 bags
Concrete Cost Estimates
| Project Size | Cubic Yards | Concrete Cost (approx) |
|---|---|---|
| Small patio | 1.5 | $150-200 |
| Driveway | 7 | $700-900 |
| Large driveway | 20 | $2,000-2,500 |
| Garage slab | 10 | $1,000-1,300 |
Cost per cubic yard: $100-150 (varies by region)
Includes: Concrete only. Delivery, reinforcement, and labor are extra.
Footing Calculator
For footings, use the same formula but measure depth instead of thickness.
Example: Continuous footing
- Length: 100 ft
- Width: 1 ft
- Depth: 1.5 ft (18 inches)
- Volume = 100 × 1 × 1.5 = 150 ft³ = 5.6 yd³
Wall Calculator
For concrete walls:
- Length: 20 ft
- Height: 8 ft
- Thickness: 0.5 ft (6 inches)
- Volume = 20 × 8 × 0.5 = 80 ft³ = 2.96 yd³
Frequently Asked Questions (FAQs)
1. How many cubic yards do I need for a 10×10 slab at 4 inches?
10 × 10 × (4÷12) = 33.3 ft³ ÷ 27 = 1.23 yd³.
2. How many 80 lb bags of concrete make a yard?
45 bags (0.6 ft³ per bag × 45 = 27 ft³).
3. How much does concrete cost per cubic yard?
$100-150 per yard for concrete only. Delivery fee extra.
4. What is the formula for concrete volume?
Volume (yd³) = Length (ft) × Width (ft) × Thickness (ft) ÷ 27.
5. How much concrete do I need for a 24×24 garage slab?
24×24=576 sq ft × (4÷12)=192 ft³ ÷27=7.11 yd³.
6. How many square feet does a yard of concrete cover at 4 inches?
27 ft³ ÷ (4÷12) = 27 ÷ 0.333 = 81 sq ft.
7. What is the waste factor for concrete?
Add 5-10% for spillage, uneven ground, and formwork gaps.
8. How deep should a concrete slab be?
Patios: 4 inches. Driveways: 5-6 inches. Garages: 4-6 inches.
9. How do I calculate concrete for a circular slab?
Area = π × radius². Then multiply by thickness.
10. What is the difference between cubic feet and cubic yards?
1 cubic yard = 27 cubic feet. 1 cubic foot = 0.037 cubic yards.
Common Mistakes
Mistake #1: Forgetting to convert inches to feet
Thickness must be in feet. Divide inches by 12.
Mistake #2: Not adding waste
Always add 5-10% for spillage and uneven ground.
Mistake #3: Ordering exactly the calculated amount
You will almost certainly need more. Add waste.
Mistake #4: Confusing radius with diameter
Radius is half the diameter. A 10-foot diameter circle has a 5-foot radius.
Mistake #5: Assuming all concrete is the same
Different projects need different strengths. 3,000 PSI for patios, 4,000 PSI for driveways.
Concrete Mix Design
| Application | Strength (PSI) | Use |
|---|---|---|
| 2,500 | 2,500 | Walkways, light duty |
| 3,000 | 3,000 | Patios, slabs |
| 3,500 | 3,500 | Driveways, garages |
| 4,000 | 4,000 | Heavy driveways, foundations |
| 5,000+ | 5,000 | Industrial, commercial |
Ordering Concrete
When ordering, tell the supplier:
- Cubic yards needed
- PSI strength
- Slump (4-6 inches typical)
- Admixtures (air entrainment for cold climates)
- Delivery date and time
Short load fee: Some suppliers charge extra for orders under 3-5 yards.
Final Thoughts
Calculating concrete volume correctly saves money and prevents headaches.
My Concrete Volume Calculator gives you:
- Cubic yards, feet, and meters
- Circle and rectangle shapes
- Waste factor adjustment
- Bag count estimates
Bookmark this page. Use it for patios, driveways, footings, and walls.
The next time you need concrete, you will know exactly how much to order.
Disclaimer: This is an educational tool. Always consult a concrete supplier for final quantities.
External Links (Authority Backlinks):
- Wikipedia – Concrete{:target=”_blank” rel=”noopener noreferrer”}
- Wikipedia – Cubic yard{:target=”_blank” rel=”noopener noreferrer”}
- Wikipedia – Cubic foot{:target=”_blank” rel=”noopener noreferrer”}
Read More
- Liters to Gallons Converter – Convert Volume Instantly (Free Tool)
- Kg to Pounds Converter – Convert Kilograms Instantly (Free Tool)
- PSI to Bar Converter – Convert Pressure Units (Free Tool)
- mm to Inches Converter – Convert Millimeters Instantly (Free Tool)
- MPa to PSI Converter – Convert Pressure Units (Free Tool)
- Newton to Pound-force Converter – Convert Force Units (Free Tool)
- Meters to Feet Converter – Instant Length Conversion (Free Tool)
- Viscosity Converter – Convert cP, Pa·s, cSt & SSU (Free Tool)
- Pressure Converter – Convert PSI, bar, kPa, MPa (Free Tool)
- Beam Deflection Calculator – Structural Beam Bending (Free Tool)
- Gear Ratio Calculator – RPM, Speed & Axle Ratio (Free Tool)
- Flow Rate Calculator – Calculate GPM, CFM & L/s (Free Tool)
- Horsepower Calculator – Torque, Weight & Electric Power (Free Tool)
- Reynolds Number Calculator – Laminar or Turbulent Flow (Free Tool)
- Static Pressure Calculator – HVAC Duct Resistance (Free Tool)
- Unitskit