Concrete Calculator

Calculate cubic yards of concrete needed for slabs and footings

Project Details
Enter your measurements and requirements
$
Results
Calculated estimates for your project
Volume0.0 cubic ft
Cubic Yards Needed0.00
80lb Bags (if bagged)0
Total Cost$0.00

Additional Information

About This Concrete Calculator

Our concrete calculator helps you determine exactly how much concrete you need for slabs, footings, posts, and other projects. Whether you're pouring a patio, sidewalk, driveway, or foundation, this tool calculates cubic yards needed based on your project dimensions.

Ordering the right amount of concrete is critical - too little means a second delivery charge and potential cold joints, while too much wastes money. The calculator converts your measurements to cubic yards, which is how ready-mix concrete is sold and delivered.

This tool is designed for DIY homeowners planning concrete projects, contractors preparing estimates, and anyone asking "how much concrete do I need for a 10x10 slab?" The calculator also shows equivalent 80lb bags for smaller projects where bagged concrete may be more practical.

How to Use This Calculator

Follow these steps to calculate your concrete needs:

  1. Measure the length and width of your project area in feet
  2. Determine the thickness (depth) of concrete needed in inches
  3. Enter the cost per cubic yard from your local supplier
  4. Review the cubic yards needed and total cost estimate
  5. Add 5-10% extra for spillage and uneven ground
Frequently Asked Questions

How much concrete do I need for a 10x10 slab?

A 10x10 foot slab that's 4 inches thick requires approximately 1.23 cubic yards of concrete. At 6 inches thick, you'll need about 1.85 cubic yards. Most suppliers have a minimum delivery of 1 cubic yard, so for small projects you may need to use bagged concrete (about 45 80lb bags per cubic yard).

How thick should a concrete slab be?

Standard thickness depends on use: 4 inches for patios, walkways, and shed floors; 5-6 inches for driveways and garage floors; 6-8 inches for heavy equipment or RV parking. Thicker slabs handle more weight but cost more. Always check local building codes for minimum requirements.

Should I use ready-mix or bagged concrete?

Use ready-mix concrete for projects over 1 cubic yard - it's more cost-effective and ensures consistent quality. Use bagged concrete for small projects under 0.5 cubic yards like posts, small pads, or repairs. The crossover point depends on local prices, but mixing more than 30-40 bags is exhausting.

How much does concrete cost per cubic yard?

Ready-mix concrete typically costs $100-150 per cubic yard, depending on mix strength and location. Delivery fees add $50-100. Short-load fees (under 5-10 yards) add $15-50 per yard. For comparison, bagged concrete costs $150-200 per cubic yard but with more labor. Get quotes from multiple suppliers.

Do I need rebar in my concrete?

Rebar or wire mesh reinforcement is recommended for driveways, garage floors, and structural applications. It helps control cracking and adds strength. For patios and walkways on stable ground, fiber mesh in the concrete mix may suffice. Always use rebar for footings and any load-bearing concrete.

How long does concrete take to cure?

Concrete reaches about 70% strength in 7 days and full strength in 28 days. You can walk on it after 24-48 hours and drive on it after 7 days for light vehicles. Keep concrete moist for the first week for best curing - cover with plastic or use curing compound.

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