How to use it
- Enter the length, width and thickness of the slab in the fields provided.
- Click the Calculate button.
- Read the cubic yards, cubic feet and bag count results.
What it does – You input the slab’s length, width and thickness. The tool instantly converts those dimensions into three practical units: cubic yards (the standard for ordering bulk concrete), cubic feet (useful for estimating material on‑site), and the number of 80‑lb bags (the most common retail size).
Why it matters – Ordering too little means project delays; ordering too much wastes money and space. Seeing all three figures lets you compare bulk delivery versus bagged mix and choose the most cost‑effective option.
How to read the results – Cubic yards = total volume ÷ 27. Cubic feet = total volume in feet. Bags = cubic feet ÷ 0.6, rounded up to the nearest whole bag. For a 12 ft × 10 ft slab 4 in thick you get 1.48 yd³, 40 ft³, and ≈ 67 bags. Use the figures to request a precise quote from your concrete supplier or to plan how many bags to load onto a truck.
Pro tips
- Add 5‑10% extra for waste and spillage
- Round bag count up to the next whole bag
- Compare bulk delivery price vs. bag price before ordering
- Double‑check thickness units—convert inches to feet before calculating
Real-life examples
- A homeowner pouring a 10 ft × 12 ft patio needs to know how many bags to buy
- A contractor estimating concrete for a 20 ft × 30 ft warehouse floor
- A landscaper ordering material for a raised garden bed
Case study
Mike entered his 14 ft × 16 ft driveway dimensions with a 5‑in thickness, got 2.2 cubic yards, 60 cubic feet and 100 bags, ordered exactly that amount, and finished on schedule without excess material.