Formula For Figuring Concrete Yardage Calculator

Instantly calculate concrete yardage, bags needed, and cubic feet for free.

  • Free
  • No sign-up
  • Instant results

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How to use it

  1. Enter length in feet.
  2. Enter width in feet.
  3. Enter thickness in inches.
  4. Read cubic yards, bags, and cubic feet results.

What it does – The Concrete Yardage Calculator takes the length, width, and thickness of your pour and instantly converts them to three practical measures: total cubic yards, total cubic feet, and the number of 80‑lb bags required. Why it matters – Knowing the exact volume prevents costly over‑orders and avoids running short mid‑project. How to read the results – Cubic yards give you the bulk quantity for ordering, cubic feet let you compare against site dimensions, and the bag count tells you how many standard mixes to purchase. The tool uses the industry standard that one 80‑lb bag yields about 0.6 ft³, and it automatically converts cubic feet to cubic yards (27 ft³ = 1 yd³). No guesswork, just clear numbers you can act on. You can save time and money by trusting these precise calculations before you place your order.

Pro tips

  • Add a 10% waste allowance to the bag total.
  • Round up the bag count to the nearest whole bag.
  • Order one extra bag for spillage or unexpected loss.
  • Double‑check that thickness in inches is correctly converted to feet.

Real-life examples

  • Homeowner pouring a 12×10 ft patio 4 in thick.
  • Contractor estimating concrete for a 30×20 ft warehouse slab 6 in thick.
  • DIY gardener building an 8×6 ft retaining wall base 5 in thick.

Case study

Mike needed a 12×10 ft patio at 4 in depth. Using the calculator he saw he required 1.5 yd³ (≈40 ft³) and 67 bags, ordered exactly that amount, and finished on schedule without extra trips.

Frequently asked questions

How do I convert thickness from inches to feet?
Divide the inches by 12; the calculator does it for you.
Why does the bag count not match the exact cubic feet?
Bags are whole units; the tool rounds up to ensure you have enough material.
Is the 0.6 ft³ per 80‑lb bag accurate for all mixes?
It’s the industry average for standard mixes; specialty mixes may vary slightly.
Can I use the results for ordering ready‑mix concrete?
Yes, the cubic‑yard figure matches what ready‑mix suppliers quote.
Do I need to include a waste factor?
Add about 10 % to the bag count to cover spillage and minor errors.