How to use
- Fill the fields with numbers you measured or were quoted.
- Click Calculate.
- Change one input and run it again. The interesting answer is the difference.
- If a handbook or a product label disagrees, believe that, not this page.
Concrete is sold by the cubic yard in the US. A yard is 27 cubic feet. Thickness in inches has to become feet before you multiply, which is why a 4-inch slab is not 4 times a 1-foot slab.
Worked example. 12 by 10 feet at 4 inches is 40 cubic feet, or 1.48 yards. Ten percent waste makes 1.63 yards. A truck often has a minimum. Ask the plant before you celebrate a small number.
This is a rectangle slab. Steps, footings, and a slope need their own measurements. Do not stretch this form over a whole foundation and call it a bid.
FAQ
Does this need an account?
No.
Is this official?
No. It uses the numbers you type.
Can I share the result?
Yes. We do not keep a copy.
What if my policy differs?
The handbook, the can, or the quote wins over this page.
Where does the file go?
Nowhere. The page runs in your browser.