How to use it
- Enter length in feet, width in feet, and thickness in inches.
- Click Calculate to see cubic yards, cubic feet, and bag count.
- Use the results to order the right amount of concrete.
The Paving Slab Calculator turns your slab dimensions into three practical measures: total cubic feet, cubic yards (the standard delivery unit), and the number of 80‑lb bags needed. Knowing the exact volume prevents over‑ordering, which saves money, and under‑ordering, which delays projects. For example, a 10 ft × 5 ft slab 4 in thick equals 16.65 ft³, or 0.62 yd³, requiring about 28 bags (16.65 ÷ 0.6). The output is instant, so you can compare prices, schedule deliveries, and adjust dimensions before any concrete is mixed. Read the cubic‑yard figure to confirm delivery size, the bag count for purchase, and the cubic‑foot total for any extra calculations.
Pro tips
- Add 5‑10% extra for waste and spillage.
- Round bag count up to the next whole bag.
- Order a little more if you plan to pour a border or edging.
- Double‑check thickness conversion; 12 in = 1 ft.
Real-life examples
- Homeowner budgeting concrete for a new driveway.
- Contractor estimating material for a commercial parking pad.
- Landscape designer sizing a patio slab for a client.
Case study
Sam entered a 12 ft × 8 ft × 5 in slab and the calculator showed 4.4 yd³ and 73 bags. He ordered 75 bags, avoided a costly short‑fall, and completed his patio on schedule.