How to use it
- Enter length, width and thickness in the fields provided.
- Click the Calculate button.
- Read the cubic yards, cubic feet and bag count results.
The Concrete Conversion Calculator turns the three dimensions you enter—length (ft), width (ft) and thickness (in)—into the three quantities you actually order: cubic feet, cubic yards, and 80‑lb bags of mix. Knowing cubic feet tells you the exact volume, while cubic yards is the unit most suppliers quote. Dividing the cubic‑foot volume by 0.6 ft³ per bag gives the bag count, so you never over‑order or run short. The results appear instantly, letting you compare prices, plan deliveries, and adjust the slab size before any material is purchased. Use the numbers to fill out supplier quotes, schedule site crews, and keep waste under control. The cubic‑yard figure is shown to two decimal places; multiply by 27 if you need the exact cubic‑foot volume again. Bag totals are rounded up because you can’t order a fraction of a bag.
Pro tips
- Add 5‑10% extra volume for spillage and uneven subgrade.
- Always round bag count up to the next whole bag.
- Order bags early; concrete sets in 90 minutes after mixing.
- Double‑check thickness conversion (inches to feet) before entering.
Real-life examples
- A homeowner pouring a 4 × 8 ft patio 4 in thick.
- A contractor estimating concrete for a 30 × 60 ft warehouse floor 6 in thick.
- A landscaper calculating material for a raised garden bed 3 ft long, 2 ft wide, 2 in thick.
Case study
Mike needed to pour a 6 × 12 ft driveway 4 in thick. Using the calculator, he saw he required 1.78 cubic yards, which translated to 84 bags. He ordered 85 bags, avoided a costly short‑fall, and finished on schedule.