A 10 × 14 ft slab 4 inches thick needs 1.73 cubic yards of concrete — 86 bags of 80-lb mix (or 115 × 60-lb), including 10% extra.
| Bag | Bags | Est. cost |
|---|---|---|
| 40 lb · 0.3 ft³ | 172 | — |
| 50 lb · 0.375 ft³ | 137 | — |
| 60 lb · 0.45 ft³ | 115 | $558 |
| 80 lb · 0.6 ft³ | 86 | $510 |
At these prices a truck becomes cheaper from about 3.25 yd³ (147 bags). Over 1–2 yd³, a truck also saves hours of mixing: plan on 3–4 minutes per bag in a mixer.
Typical U.S. big-box prices checked October 2026. Tap any price to enter your store's.
| Thickness | Cubic yards | 80-lb bags | 60-lb bags | Bag cost | Ready-mix |
|---|---|---|---|---|---|
| 3.5 in (2×4) | 1.51 | 75 | 100 | $445 | $613 |
| 4 in | 1.73 | 86 | 115 | $510 | $655 |
| 5 in | 2.16 | 107 | 143 | $635 | $740 |
| 6 in | 2.59 | 129 | 172 | $765 | $825 |
10 ft × 14 ft = 140 sq ft. Multiply by the thickness in feet (4 ÷ 12 = 0.333 ft) to get 46.67 cubic feet, and divide by 27 for 1.73 cubic yards.
Adding 10% for uneven ground and spillage gives 51.33 cu ft. Quikrete and Sakrete both rate an 80-lb bag at 0.6 cu ft, so 51.33 ÷ 0.6 = 85.6, rounded up to 86 bags.
Ready-mix is priced at about $170 per yard for 4,000 psi plus delivery, fuel and — under 4 yards — a short-load fee. Plants sell in quarter-yard steps, so the order is 2 yd³.
The full method, material data and tips are on the main concrete slab calculator page.