Concrete calculator
Yards for the ready-mix truck or bags for the mixer. Sidewalks run 4 inches; driveways 5 to 6 inches over a compacted base.
To work out how much concrete you need, multiply length by width by depth in feet and divide by 27: that is cubic yards. A cubic yard is 27 cubic feet, so at 0.6 cu ft a bag that is about 45 80 lb bags to the yard. Order about 10 percent over the calculated number for compaction, spillage and uneven grade.
Pro habit: Past about 1 yard (2.7 yd³ with cushion here), call for ready-mix; that is roughly 45 bags per yard and your back will know it.
Order a cushion on ready-mix; coming up half a yard short on a monolithic pour is the expensive kind of short. Many plants have minimum-load fees below 3 or 4 yards. Weights are common industry approximations; confirm with your supplier before ordering.
The number above assumes a few things about how this material behaves in the ground.
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TrackOver runs dirt-work companies: jobs, crews, stamped site photos, machine hours, and billing in one place. Built inside a working excavation company.
Common questions
How do I calculate how much concrete I need?
Multiply length by width by depth in feet, then divide by 27 to get cubic yards. This concrete calculator does it for you: enter length and width in feet and depth in inches, and it returns cubic yards. Add about 10 percent for compaction, spillage, and uneven grade.
How many 80 lb bags are in a cubic yard?
A cubic yard is 27 cubic feet, so at 0.6 cu ft per bag that is about 45 80 lb bags per yard. Past roughly a yard, buying in bulk usually beats bags on price and effort.
Is this concrete calculator free?
Yes. It is a free tool from TrackOver, software built inside a working excavation company for contractors who move dirt. No signup required to use it.
TrackOver keeps the job, the photos, the hours and the invoice in one place, on the office screen and every crew phone.
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