Skip to content
HammerCalc

How much concrete for a 10 × 12 slab?

A 10x12 slab is 120 sq ft. At the standard 4-inch depth it takes 1.63 cubic yards of concrete (74 80 lb bags) including the recommended 10% waste factor.

Thickness Cubic yards (incl. 10% waste) 80 lb bags 60 lb bags
4 in (patio, shed base)1.63 yd³7498
5 in (light vehicles)2.04 yd³92123
6 in (driveway, garage)2.44 yd³110147
You need approximately
1.63 cubic yards
Slab area120 sq ft
Volume incl. 10% waste1.63 yd³ (44 ft³)
80 lb bags (0.60 ft³ each)74 bags
60 lb bags (0.45 ft³ each)98 bags
Formula shown below

Estimates are for planning. Confirm quantities against your measured site and product packaging before ordering, and follow local building codes.

Bags or ready-mix for a 10x12 slab?

At 1.63 cubic yards for the 4-inch pour, ready-mix delivery is the realistic choice: that volume means hand-mixing 74 bags, which is a full day of brutal work and risks cold joints between batches. Expect roughly $244 – $359 for the concrete delivered at 2026 prices ($150 to $220 per cubic yard), and ask about the short-load fee, which can add $50 to $150 on small pours. The formula behind these numbers is on the concrete calculator: length × width × depth, converted to cubic yards, plus your chosen waste factor.

Before ordering, prepare a compacted gravel base of 4 inches (see the gravel calculator for quantities) and read what a finished slab really costs for forms, labor, and finishing on top of the material price.

Frequently asked questions

How many bags of concrete do I need for a 10x12 slab?

At 4 inches thick, a 10x12 slab needs about 74 80 lb bags or 98 60 lb bags, including 10% waste. At 120 sq ft, ready-mix delivery is usually more practical than mixing bags.

How much does concrete for a 10x12 slab cost?

The concrete alone for a 10x12 slab at 4 inches (1.63 cubic yards) runs roughly $244 – $359 delivered at typical 2026 ready-mix prices of $150 to $220 per cubic yard, before any short-load fee. A finished slab with labor, forms, and base costs several times the material.

Should a 10x12 slab be 4 or 6 inches thick?

Four inches suits patios, walkways, and shed bases. Go to 5 or 6 inches if the slab will carry vehicles or heavy point loads. The jump from 4 to 6 inches adds about 50% more concrete.