Cost concrete calculator
What you need
4.94 cu yd
- Cubic feet
- 133.33 cu ft
- Cubic metres
- 3.776 m³
- Order this much
- 5.43 cu yd
- 80 lb bags
- 245
- 60 lb bags
- 326
- Weight
- 18,670 lb
- Truckloads
- 1
- Cost
- $850 to $1,150
Common sizes
| Size | Cubic yards | 80 lb bags |
|---|---|---|
| 12×12 | 1.78 | 89 |
| 20×20 | 4.94 | 245 |
| 24×24 | 7.11 | 353 |
| 30×30 | 11.11 | 550 |
| 30×40 | 14.81 | 734 |
| 40×60 | 29.63 | 1,467 |
How this is worked out
volume in cubic feet = width in feet × length in feet × thickness in inches ÷ 12
cubic yards = cubic feet ÷ 27
bags = cubic feet with waste ÷ what one bag yields, rounded up
At the dimensions above that is 133.33 cubic feet, which is 4.94 cubic yards.
Questions
How much concrete do I need for a 20 × 20 ft slab 4 in thick?
4.94 cubic yards, which is 133.33 cubic feet before any waste allowance.
How many bags of concrete is that?
245 eighty-pound bags, or 326 sixty-pound bags, with 10% waste allowed for.
How much does that much concrete cost?
About $850 to $1,150 at $184 per cubic yard delivered. Prices vary by region, so enter a quote of your own to replace the default.
Is that a full truckload?
It is 1, once waste is allowed for. A full truckload is typically about 10 cubic yards.
This site works out quantities. It does not tell you what thickness, reinforcement or sub-base your job needs — those depend on local code and on the load.
Other calculators
Where these numbers come from
Bag yields: QUIKRETE Concrete Mix data sheet No. 1101. Price basis: Concrete Financial Insights weighted average selling price for 2025, escalated with U.S. Bureau of Labor Statistics PPI series PCU327320327320 (2026-06). Prices vary by region — enter your own quote above.