How to use it
- Enter length, width, and thickness in the fields provided.
- Enter your price per cubic yard.
- Click Calculate to see cubic yards, bags, cubic feet, and estimated cost.
What it does – The calculator turns the dimensions of your slab (length, width, thickness) and the local price per cubic yard into four clear numbers: total cubic feet, cubic yards, how many 80‑lb bags you’ll need, and the estimated material cost.
Why it matters – Knowing the exact volume prevents over‑ordering, saves money, and helps you schedule delivery. A small mis‑calculation can add dozens of extra bags or leave a pour short.
How to read the results – Cubic feet is the raw volume; divide by 27 to get cubic yards, the unit most suppliers quote. Bags are the volume in cubic feet divided by 0.6 (the yield of one 80‑lb bag). Multiply the cubic yards by your price to see the estimated cost. Adjust the numbers if you add a waste factor.
Pro tips
- Add 5‑10% waste to volume for cuts and spillage.
- Round up bag count to the next whole bag.
- Compare at least three suppliers using the cubic‑yard total.
- Double‑check thickness conversion (inches to feet) before entering.
Real-life examples
- A homeowner planning a 12 ft × 10 ft patio 4 in thick.
- A contractor estimating concrete for a 30 ft × 40 ft warehouse floor.
- A landscape designer budgeting for a 6 ft × 8 ft garden path 3 in thick.
Case study
Mike needed a 200 sq ft driveway 5 in thick. Using the calculator he saw the pour required 2.2 cubic yards, 4 bags, and $220 material cost, letting him order exactly what he needed and avoid a $150 overrun.