Estimate slab concrete before you call a ready-mix plant or decide whether bags are enough.
Planning calculator only. Do not rely on this page alone for structural design, permitting, code compliance, engineering signoff, procurement quantities, or contractual commitments.
Enter slab length and width in feet, thickness in inches, then get ready-mix yards plus dry-bag estimates.
Enter job values, review the estimate, then use the decision hints before ordering or quoting.
| length | width | thickness Inches | yards |
|---|---|---|---|
| 20 | 30 | 4 | 7.41 |
| 12 | 16 | 6 | 3.56 |
Volume (cu ft) = Length × Width × ThicknessThickness is converted from inches to feet, then volume is translated to cubic yards for ordering.
Order quantity shown includes 10% waste. Bag yields are approximate: 80 lb ≈ 0. 60 cu ft, 60 lb ≈ 0. 45 cu ft.
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