Calculator
Concrete Calculator
Enter the slab size and thickness. You get cubic yards for a ready-mix order, the number of 60 or 80 lb bags, and how far apart to cut control joints.
Enter the slab size and thickness. You get cubic yards for a ready-mix order, the number of 60 or 80 lb bags, and how far apart to cut control joints.
Volume is length times width times thickness. Thickness is in inches, so it is divided by 12, and cubic feet are divided by 27 for cubic yards.
Ready-mix is ordered in cubic yards. We round up to the next quarter yard after adding the extra you set for an uneven base and spillage.
Bags use Quikrete's yields: an 80 lb bag of Concrete Mix makes about 0.60 cubic feet and a 60 lb bag about 0.45. Past a cubic yard (about 45 80 lb bags), most jobs order a truck instead.
Control joints keep cracks in straight lines. NRMCA's guidance is a spacing of 24 to 36 times the slab thickness, never more than 15 ft, with panels close to square.
Estimates only. Measure carefully and confirm quantities with your supplier or contractor before ordering.
4 in is the usual thickness for patios and walks with foot traffic. Driveways usually go thicker. Check what the job needs before you order.
Not for a concrete or brick patio or walk on private property that is not over a basement and not more than 30 in above grade. City sidewalks, curbs and driveway aprons need a CDOT permit.
About 45 bags of 80 lb mix or 60 bags of 60 lb mix, using Quikrete's yields.
Every 24 to 36 times the slab thickness: about 8 to 10 ft for a 4 in slab, with panels as close to square as you can make them.
Calculators get you close. A free on-site estimate gets you the price. We answer in English and Spanish.
Your calculator results are added to the message.