Weight is just volume times density
Ordinary concrete weighs about 150 pounds per cubic foot. The whole calculation is your volume multiplied by that density. The one thing to get right is the volume unit: a cubic yard is 27 cubic feet, so a yard of concrete is 27 × 150 = 4,050 lb, about 2 short tons.
Common volumes, by weight
| Volume | Pounds | Short tons | Metric |
|---|---|---|---|
| 1 ft³ | 150 lb | 0.08 | 68 kg |
| 10 ft³ | 1,500 lb | 0.75 | 680 kg |
| 1 yd³ (27 ft³) | 4,050 lb | 2.0 | 1.84 t |
| 1 m³ | 5,300 lb | 2.65 | 2,400 kg |
| 4-inch slab, 100 ft² | 5,000 lb | 2.5 | 2,270 kg |
A standard mixer truck carries about 10 cubic yards, roughly 40,000 lb of concrete — near the legal load limit, which is why full trucks are common.
Density depends on the mix
- Normal / structural. 150 lb/ft³ (2,400 kg/m³) — the default for slabs, footings and columns.
- Lightweight. 90 to 120 lb/ft³, using air pockets or lightweight aggregate to cut structural load by 20 to 40%.
- Reinforced. About 152 lb/ft³. Rebar barely moves the number — 1% steel adds only 1 to 2%.
The unit trap
The most common error is mixing cubic feet and cubic yards. They differ by a factor of 27, so a slip turns a 4,050 lb yard into a nonsense number.
A cubic yard holds 27 times the concrete of a cubic foot. Confirm which unit your volume is in before you multiply.
Common questions
How much does a cubic yard of concrete weigh?
About 4,050 pounds, or roughly 2 short tons. That is 27 cubic feet at the standard 150 pounds per cubic foot. A cubic meter comes to about 2,400 kilograms.
What density should I use for concrete?
Use 150 lb/ft3 for ordinary structural concrete. Lightweight mixes run 90 to 120, and adding rebar lifts it only slightly, to about 152. The ACI 318 code fixes normal-weight concrete at 150 give or take 5.
Does concrete get lighter as it dries?
Yes, a little. Fresh concrete carries extra mixing water and can lose 8 to 12% of its weight over about 90 days as that water evaporates. The 150 lb/ft3 figure is for cured concrete.
