12x24 Concrete Slab: Bags, Yards & Cost

A 12 × 24 ft slab (288 sq ft) 4 in thick is 96.0 cu ft, or 3.56 cu yd: 160 bags of 80 lb Quikrete Concrete Mix (168 with a 5% margin), 214 bags of 60 lb, or 105 bags of 80 lb Sakrete Maximizer. The 80 lb bags weigh 12,800 lb in total.

Your cost and bags vs a truck

Set up for: a 12 × 24 ft slab · Different project?

12x24 slab at 4, 5 and 6 inches

ThicknessCu ydWith 5%80 lb Quikrete60 lb Quikrete80 lb Maximizer80 lb 5000 Plus
4 in3.563.73160214105160
5 in4.444.67200267131200
6 in5.335.60240320157240

Whole bags without margin, from each maker's published yield. The thickness comes from your plans; we don't recommend one.

Other sizes: 10x10 · 12x12 · 20x20 · 8x8 · 10x12 · 30x30 · 8x10 · 12x36 · 20x30 · 20x40

FAQ

How many bags of concrete for a 12x24 slab?

At 4 in thick: 160 bags of 80 lb Quikrete Concrete Mix or 214 of 60 lb (whole bags, no margin). At 6 in: 240 of 80 lb.

How many yards of concrete for a 12x24 slab?

3.56 cu yd at 4 in, 4.44 at 5 in and 5.33 at 6 in, before the 4–10% NRMCA suggests adding when you order.

How much does a 12x24 concrete slab cost?

We don't publish prices because they change by store and region. Multiply 160 bags by your store's 80 lb bag price, or 3.73 cu yd (4 in, with 5%) by your plant's price per yard plus delivery and short-load fees. Type those into the calculator to compare.

Sources

Volumes only. ConcreteMath calculates volumes, bag counts, weights and your own cost figures. It gives no structural or engineering advice and never sizes footings, piers, slabs or rebar: those come from your plans, an engineer or your local building department. Bag counts are estimates from each maker's published yield; actual use varies with hole shape, uneven ground, waste and mixing. Bulk weights are published ranges; your supplier's figure wins.