Sakrete Concrete Mix Calculator

Instantly calculate how many cubic yards, bags, and cubic feet of concrete you need for any slab—free and instant.

  • 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 Sakrete Concrete Mix Calculator turns your slab dimensions (length, width, thickness) into three useful numbers: cubic yards of concrete, the number of 80‑lb bags required, and total cubic feet. Why it matters – Ordering the right amount saves money and prevents delays; too little means a weak pour, too much adds unnecessary cost and waste. How to read the results – Cubic yards is the volume contractors use for delivery quotes. Bags tells you how many 80‑lb sacks to purchase; always round up to the next whole bag. Cubic feet is a quick check against your own measurements. No hidden formulas—just the standard 0.6 ft³ per bag and the 27 ft³ per yard conversion. You can also compare the bag count with supplier minimum orders to avoid extra trips. The calculator updates instantly as you change any dimension, so you can experiment with thickness before you commit.

Pro tips

  • Add 10% extra for spillage and uneven subgrade.
  • Round bag count up; you can’t buy a fraction of a bag.
  • Order bags in multiples that match supplier delivery minimums.
  • Double‑check thickness; a common mistake is entering inches as feet.

Real-life examples

  • Homeowner pouring a 12‑ft patio slab 4 in thick.
  • Contractor estimating concrete for a 24‑ft driveway 6 in thick.
  • DIY hobbyist building a garden stepping stone base 3 in thick.

Case study

Mike needed a 10 × 10 ft patio 4 in thick. Using the calculator he saw he required 1.24 cubic yards, which translates to 56 bags of Sakrete mix. He ordered 56 bags, avoided a second delivery, and completed the pour on schedule, saving $120 on material waste.

Frequently asked questions

How many 80‑lb bags are needed for a 5 ft thick slab?
Enter the dimensions; the calculator will divide total cubic feet by 0.6 to give the bag count, then round up.
What is the difference between cubic feet and cubic yards?
One cubic yard equals 27 cubic feet; the tool shows both for ordering and delivery purposes.
Do I need to add waste to the bag total?
Yes, add about 10% extra to the bag result to cover spillage and minor errors.
Can I use the calculator for vertical walls?
It’s designed for horizontal slabs; for walls you’d need to input wall area and thickness similarly.
Why does the calculator round up the bag number?
Bags are sold whole; rounding up ensures you have enough mix to finish the project.