Concrete Weight Calculator
Concrete weighs about 150 lb per cubic foot, or 4,050 lb per cubic yard. Enter your slab, footing or column to get its weight.
Last updated November 13, 2026
How much does concrete weigh?
Normal-weight concrete weighs about 150 lb per cubic foot. Multiply your volume in cubic feet by 150 to get the weight in pounds.
| Volume | Weight |
|---|---|
| 1 cubic foot | 150 lb |
| 1 cubic yard (27 cu ft) | 4,050 lb, about 2 tons |
| 1 cubic meter | about 5,300 lb (2,400 kg) |
| One 80 lb bag, mixed (0.60 cu ft) | about 90 lb |
Weight of a concrete slab
For a slab, weight per square foot depends only on thickness.
| Thickness | Weight per square foot | 10 × 10 ft slab | 20 × 20 ft slab |
|---|---|---|---|
| 4 in | 50 lb | 5,000 lb | 20,000 lb |
| 5 in | 62.5 lb | 6,250 lb | 25,000 lb |
| 6 in | 75 lb | 7,500 lb | 30,000 lb |
| 8 in | 100 lb | 10,000 lb | 40,000 lb |
The formula
Weight (lb) = length × width × thickness × 150, with every measurement in feet. A 12 ft × 12 ft slab at 4 inches is 12 × 12 × 0.333 × 150 = 7,200 lb.
Why the number varies
- Mix: plain concrete is often taken as 145 lb per cubic foot and reinforced concrete as 150 lb. This calculator uses 150.
- Lightweight concrete: mixes made with lightweight aggregate run roughly 90 to 115 lb per cubic foot.
- Water: freshly placed concrete is slightly heavier than cured concrete because some mixing water evaporates.
If the weight matters for a deck, a truck bed or a lift, confirm the density with your supplier. For quantities, use the concrete yard calculator.
Normal weight concrete and pcf
Engineers quote the weight of concrete as a density in pcf, which means pounds per cubic foot. Normal weight concrete is about 145 pcf plain and about 150 pcf once steel reinforcement is included. This concrete weight calculator uses 150 pcf, the usual figure for estimating. Lightweight concrete, made with expanded shale or similar aggregate, is noticeably lighter, commonly in the range of 90 to 115 pcf. If your mix supplier gives you a density, use theirs.
Weight of concrete by the truckload
| Cubic yards | Weight at 150 pcf | In tons |
|---|---|---|
| 1 | 4,050 lb | 2.0 |
| 3 | 12,150 lb | 6.1 |
| 5 | 20,250 lb | 10.1 |
| 9 | 36,450 lb | 18.2 |
| 10 | 40,500 lb | 20.3 |
Multiply cubic yards by 4,050 to get pounds. Nine yards of concrete, a common single-truck order, weighs 36,450 lb before you count the truck.
Concrete slab weight by dimensions
To find a concrete slab weight from its dimensions, multiply length × width × thickness in feet to get cubic feet, then multiply by 150. A 12 × 20 ft slab at 4 inches is 80 cubic feet, so it weighs 12,000 lb. Per square foot, that is 12.5 lb for every inch of thickness.
Crushed concrete, blocks and rebar
- Crushed concrete. A yard of crushed concrete weighs far less than a yard of solid concrete, because the pile is full of air gaps. It is sold by the ton and each supplier has its own tons-per-yard figure. Enter theirs in the crushed concrete calculator.
- CMU block weight. A standard hollow 8 × 8 × 16 in concrete block typically weighs somewhere between 30 and 38 lb depending on the mix, and lightweight block is less. Check the supplier’s spec sheet for the exact unit. Count the blocks with the concrete block calculator.
- Rebar. How much does rebar weigh? #3 bar is 0.376 lb per foot, #4 is 0.668 lb per foot and #5 is 1.043 lb per foot. The full table is in the rebar weight chart.
Frequently asked questions
How much does a yard of concrete weigh?
About 4,050 lb, or roughly 2 tons. That is 150 lb per cubic foot multiplied by the 27 cubic feet in a yard.
How much does concrete weigh per cubic foot?
Normal-weight concrete weighs about 150 lb per cubic foot. Plain concrete is often taken as 145 lb and reinforced concrete as 150 lb.
How much does a 4-inch concrete slab weigh per square foot?
About 50 lb per square foot. A 6-inch slab weighs about 75 lb per square foot.
How much does a 10×10 concrete slab weigh?
A 10 ft by 10 ft slab at 4 inches thick is 33.3 cubic feet and weighs about 5,000 lb.
How much does a cubic meter of concrete weigh?
About 2,400 kg, or roughly 5,300 lb.
What is normal weight concrete?
Concrete made with ordinary sand and gravel, weighing about 145 to 150 pounds per cubic foot. Lightweight concrete uses lighter aggregate and weighs less.
How much does 9 yards of concrete weigh?
About 36,450 lb, or roughly 18 tons, at 150 pounds per cubic foot.
What does pcf mean?
Pounds per cubic foot. It is the unit used for concrete density. Normal weight concrete is about 150 pcf.