How to use it
- Enter length in feet.
- Enter width in feet.
- Enter thickness in inches.
- Enter price per cubic yard and click Calculate.
What it does – The calculator turns your slab dimensions and material price into four actionable numbers: total cubic yards of mix, the estimated dollar cost, how many 80‑lb bags you’ll need, and the volume in cubic feet. Why it matters – Knowing cubic yards prevents over‑ordering, saves money, and ensures you have enough material to finish without delays. Reading the results – Cubic yards is the standard ordering unit for ready‑mix; multiply by your price to see cost. Bags tells you how many pre‑mixed bags to buy if you’re using bagged mix (each bag = 0.6 ft³). Cubic feet helps you compare against other projects. Example – A 10 ft × 10 ft slab 4 in thick equals 1.24 yd³, about 56 bags, and costs $148 if price is $120/yd³.
Pro tips
- Add 5‑10% extra for spillage and settling.
- Round up bag count to the next whole bag.
- Order a little more than calculated if delivery lead time is long.
- Double‑check thickness; a common mistake is entering inches as feet.
Real-life examples
- A homeowner estimating concrete for a new patio.
- A contractor pricing a garage floor pour.
- A landscape designer calculating material for a retaining wall base.
Case study
John needed a 12 ft × 8 ft patio 5 in thick. Using the calculator he saw he required 1.48 yd³, about 67 bags, and a $177 cost at $120/yd³, letting him order precisely and stay on budget.