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
Estimates only — material density varies with type, moisture and compaction. Order a little extra and confirm with your supplier. 🔒 Calculated in your browser.
🔒 Nothing you enter is sent anywhere or stored. All processing happens in your browser.
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.
How it works — in four simple steps
No signup, 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.
How it works
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.