Key takeaways
- QUIKRETE lists its Concrete Mix at about 140 lb per cubic foot.
- That works out to about 3,780 lb per cubic yard.
- Use this for planning, not to decide whether a floor or vehicle can carry a load.
Enter the slab's size and thickness. The result uses about 140 lb per cubic foot, the typical unit weight QUIKRETE publishes for its Concrete Mix.
How the calculator works
- Cubic feet: length × width × (thickness ÷ 12)
- Weight: cubic feet × 140 lb
- Tons: pounds ÷ 2,000
For example, a 10 × 12 foot slab, 4 inches thick, is 40 cubic feet. That's 40 × 140 = 5,600 lb, or 2.8 tons.
Concrete weight chart
| Amount | Approximate weight |
|---|---|
| 1 cubic foot | 140 lb |
| 1 cubic yard | 3,780 lb (1.89 tons) |
| 100 sq ft slab, 4 in thick | 4,667 lb |
| 100 sq ft slab, 6 in thick | 7,000 lb |
Why your concrete may differ
This is a typical figure for one product. Weight varies with the mix and its ingredients, so ask your supplier or an engineer if the exact number matters.
When weight matters
- Delivery and handling: check whether your vehicle, trailer or wheelbarrow route can take the load. Your vehicle's manual and trailer's rating set the limits.
- Removal: a disposal or demolition quote may depend on weight, so ask how yours is priced.
- Structures: don't use this to decide whether a floor, deck or roof can carry a slab. That's a question for an engineer.
To work out the amount of concrete instead, use the concrete slab calculator.
Worked example: hauling bags
Weight limits usually come up with the dry bags. Forty 80 lb bags weigh 3,200 lb, which can be more than a pickup's rated payload. Check the figure in your vehicle's manual or door label, and split the load or arrange delivery if needed.
Frequently asked questions
How much does a cubic foot of concrete weigh?
About 140 lb, based on QUIKRETE's typical figure for its Concrete Mix.
How much does a yard of concrete weigh?
About 3,780 lb, or 1.89 tons, at 140 lb per cubic foot.
Does an 80 lb bag make 80 lb of concrete?
Not quite: water adds weight. QUIKRETE suggests about 6 to 9 pints of water for an 80 lb bag.
Sources
We use primary sources where we can: building codes, federal rules and manufacturer documents. Read our editorial standards.
- QUIKRETE: Concrete Mix data sheet, product 1101 (unit weight, water)