A small slab
A 10 × 6 ft slab at 4 in thickness contains 20 ft³. Adding 10% gives 22 ft³. A bag yielding 0.6 ft³ of mixed concrete requires 37 bags, providing 22.2 ft³.
Compare bags by mixed yield with a bulk order rounded to your supplier’s increment.
Project measurements
Use one currency throughout; tax, labor and delivery excluded.
Prices use your chosen currency consistently. Blank price skips cost. Example coverage, density, yield and prices are editable scenarios, not current product offers.
Material takeoff
Estimated purchase quantity
37 bags
1 solid slab(s) · volume only
Illustration is schematic, not an installation drawing.
| Geometric volume | 0.74 yd³ |
|---|---|
| Volume | 0.81 yd³ |
| Cubic feet | 22 ft³ |
| Liters | 622.97 L |
| Bagged yield purchased | 22.2 ft³ |
| Bulk alternative (rounded) | 1 yd³ |
| Bagged material cost | Not entered |
Method: Area × depth × count × (1 + allowance/100). Divide by the product’s mixed yield and round up. Bulk alternative rounds volume up to the supplier increment.
Bag yield means mixed concrete volume, not dry-bag volume or bag weight. Solid shapes only: no reinforcing displacement or holes. Thickness and shape are user inputs, not design recommendations. Bulk and bag quantities are alternatives, not added together.
Quantity and material-only cost estimate. Verify field measurements, product instructions and your purchase units. Labor, delivery, taxes, equipment and structural adequacy are excluded.
Calculations run in your browser. This tool does not request a location, retrieve live prices or send your measurements to a material supplier.
How to use the Concrete Calculator
- 01
Choose a rectangular slab or solid cylinder. Enter dimensions and the number of identical shapes.
- 02
Enter mixed yield per bag from the concrete specification. Add your allowance for uneven excavation or loss.
- 03
Enter the supplier’s bulk volume increment and optional bag price. Review bag and bulk alternatives separately.
Examples
Bulk ordering
That 22 ft³ target is about 0.815 yd³. With a supplier increment of 0.25 yd³, the bulk alternative rounds to 1 yd³. The bag quantity and bulk quantity are alternative purchase methods.
Yield is volume after mixing
QUIKRETE’s training material calculates slab volume from length, width and thickness, then divides by mixed bag yield. Enter the yield for the product you will actually use. Bag weight alone is not enough, and dry package volume is not the same as mixed yield.
The shape does not select the design
A circle uses π × diameter² ÷ 4 for plan area; depth makes it a solid cylinder. No post, void, reinforcement or excavation displacement is deducted. The entered thickness is a measurement scenario, not a recommendation for a safe slab or footing.
What to know
- Material quantities and user-price scenarios only; no structural adequacy, code compliance or installation approval.
- Example product values are illustrative. Verify your measurements and current product label before ordering.
Common questions
Are post holes supported?
A round hole can be modeled as a solid cylinder, but the tool does not subtract a post and does not choose suitable hole dimensions.
Is 10% always enough extra?
No. The default is illustrative. Excavation tolerances, uneven subgrade and handling losses vary; use your own project allowance.
Can I use this for mortar or cement alone?
Only if the product’s mixed-volume yield and your required solid volume make sense for the job. It does not calculate concrete mix ratios or cement, sand and aggregate proportions.