Concrete Calculator
Work out how much concrete you need for a project — enter the area and depth, and get the volume in cubic yards and cubic feet, plus the number of bags.
Concrete Calculator
Densities are typical values — moisture, grading and compaction change them. Confirm with your supplier and round up.
Runs in your browser — nothing you enter is uploaded or stored.
Scratchpad auto-saved
How it works — in four simple steps
No signup and nothing to install — it all runs in your browser.
Measure your area
Measure the length and width in feet (or the diameter for a round area) and enter them.
Set the depth
Enter how deep you want the concrete in inches — a typical range is suggested for you.
Calculate
Read the volume in cubic yards and cubic feet, plus the bag count.
Order with a little spare
Keep the 10% waste allowance on, or add your own margin, so you don't run short.
4″ is standard for patios and walkways, 5–6″ for driveways — and always order 5–10% extra.
Features
Estimates in the units you buy
Enter the area and depth and get the volume in cubic yards and cubic feet, plus how many bags you'll need — the quantities suppliers actually sell by, so you can order with confidence.
Rectangle or circle
Works for straight rectangular areas and for round patios, fire-pit surrounds or planters — switch shape and enter the diameter.
Built-in waste allowance
A 10% extra is added by default for waste, compaction and uneven ground, so you're less likely to run short mid-job. Turn it off for an exact volume.
Ready-mix yards and bag counts
Get the volume in cubic yards for a ready-mix order, plus how many 60 lb and 80 lb bags it would take if you're mixing it yourself.
About the Concrete Calculator
Estimating concrete comes down to one idea: volume = area × depth. Measure the area you're covering (length × width, or π × radius² for a circle), multiply by how deep you want the concrete, and you have the volume. This calculator does that and converts the result into the units suppliers sell by — cubic yards, cubic feet and bags.
Depth is entered in inches because most concrete layers are only a few inches deep, while the area is in feet — the tool handles the unit conversion for you. A 10% waste allowance is added by default, since real ground is uneven and material compacts. Everything is calculated in your browser.