How to use it
- Enter length in feet.
- Enter width in feet.
- Enter thickness in inches. The results appear automatically.
What it does The Concrete Square Feet Calculator turns the dimensions of a slab—length, width, and thickness—into the three numbers you need to order concrete: total cubic feet, cubic yards, and the number of 80‑lb bags (each bag ≈ 0.6 ft³).
Why it matters Knowing cubic yards helps you get the right delivery size, while bag count tells you how many bags to buy if you’re mixing on‑site. Accurate numbers prevent costly over‑orders or shortfalls that delay projects.
How to read the results
- Cubic feet: raw volume of your slab.
- Cubic yards: divide cubic feet by 27, the standard yard conversion.
- Bags: divide cubic feet by 0.6, then round up to the next whole bag.
Pro tips
- Add 5‑10% extra for waste and spillage.
- Always round up the bag count; you can’t buy a fraction of a bag.
- Order a slightly larger delivery size if you’re near a yard‑size threshold.
- Double‑check thickness; a 1‑inch error can double the volume.
Real-life examples
- Homeowner estimating material for a new driveway.
- Contractor preparing a concrete patio quote.
- DIY enthusiast mixing a garage floor slab.
Case study
Mike needed a 12 × 24 ft patio 4 in thick. Using the calculator he saw the job required 96 ft³, 3.6 yd³ and 160 bags. He ordered 165 bags, avoided a second delivery, and finished on schedule.