Concrete Slab Sizes
Concrete for common slab sizes, each worked out with the concrete calculator: cubic yards with 10% waste, bag counts, the ready-mix order and its cost. Each page also covers bags vs ready-mix, thickness, control joints and weight for that size.
Small pads
AC units, generators, trash cans, steps and landings.
| Slab | Cu yd | 80 lb bags | Ready-mix order | Ready-mix cost |
|---|---|---|---|---|
| 4x4 slab, 4 in | 0.22 | 10 | 1 cu yd | $200 – $290 |
Patios, sheds and hot tubs
Foot traffic, furniture, sheds; 6 in for a hot tub or heavier loads.
| Slab | Cu yd | 80 lb bags | Ready-mix order | Ready-mix cost |
|---|---|---|---|---|
| 8x8 slab, 4 in | 0.87 | 40 | 1 cu yd | $200 – $290 |
| 8x10 slab, 4 in | 1.09 | 49 | 1.25 cu yd | $235 – $335 |
| 10x10 slab, 4 in | 1.36 | 62 | 1.5 cu yd | $270 – $380 |
| 10x12 slab, 4 in | 1.63 | 74 | 1.75 cu yd | $305 – $425 |
| 12x12 slab, 4 in | 1.96 | 88 | 2 cu yd | $340 – $470 |
| 12x16 slab, 4 in | 2.61 | 118 | 2.75 cu yd | $445 – $605 |
| 14x14 slab, 4 in | 2.66 | 120 | 2.75 cu yd | $445 – $605 |
| 10x20 slab, 4 in | 2.72 | 123 | 2.75 cu yd | $445 – $605 |
| 16x16 slab, 4 in | 3.48 | 157 | 3.5 cu yd | $550 – $740 |
| 16x20 slab, 4 in | 4.35 | 196 | 4.5 cu yd | $690 – $920 |
Garages and shops
Garage floors, pole barns and shop slabs that carry vehicles.
| Slab | Cu yd | 80 lb bags | Ready-mix order | Ready-mix cost |
|---|---|---|---|---|
| 12x20 slab, 4 in | 3.26 | 147 | 3.5 cu yd | $550 – $740 |
| 12x24 slab, 4 in | 3.91 | 176 | 4 cu yd | $620 – $830 |
| 20x20 slab, 4 in | 5.43 | 245 | 5.5 cu yd | $830 – $1,100 |
| 20x20 slab, 6 in | 8.15 | 367 | 8.25 cu yd | $1,215 – $1,595 |
| 24x24 slab, 4 in | 7.82 | 352 | 8 cu yd | $1,180 – $1,550 |
| 20x30 slab, 4 in | 8.15 | 367 | 8.25 cu yd | $1,215 – $1,595 |
| 24x30 slab, 4 in | 9.78 | 440 | 10 cu yd | $1,400 – $1,800 |
| 30x30 slab, 4 in | 12.22 | 550 | 12.25 cu yd | $1,715 – $2,205 |
| 30x30 slab, 6 in | 18.33 | 825 | 18.5 cu yd | $2,590 – $3,330 |
| 24x40 slab, 4 in | 13.04 | 587 | 13.25 cu yd | $1,855 – $2,385 |
| 30x40 slab, 4 in | 16.3 | 734 | 16.5 cu yd | $2,310 – $2,970 |
| 30x50 slab, 4 in | 20.37 | 917 | 20.5 cu yd | $2,870 – $3,690 |
| 40x40 slab, 4 in | 21.73 | 978 | 21.75 cu yd | $3,045 – $3,915 |
| 30x60 slab, 4 in | 24.44 | 1,100 | 24.5 cu yd | $3,430 – $4,410 |
| 40x50 slab, 4 in | 27.16 | 1,223 | 27.25 cu yd | $3,815 – $4,905 |
| 40x60 slab, 4 in | 32.59 | 1,467 | 32.75 cu yd | $4,585 – $5,895 |
| 50x50 slab, 4 in | 33.95 | 1,528 | 34 cu yd | $4,760 – $6,120 |
Driveways and parking pads
Single and double driveways and RV or parking pads.
| Slab | Cu yd | 80 lb bags | Ready-mix order | Ready-mix cost |
|---|---|---|---|---|
| 12x30 slab, 4 in | 4.89 | 220 | 5 cu yd | $760 – $1,010 |
| 20x40 slab, 4 in | 10.86 | 489 | 11 cu yd | $1,540 – $1,980 |
Materials only, national price ranges as of 2026-09, not quotes. Ready-mix costs include a short-load fee under 10 cu yd. Don't see your size? The concrete calculator takes any length, width and thickness.