Concrete weight calculator
Enter a slab or a volume you already know and this gives the weight of the pour: pounds, short tons, and kilograms. It runs the same density math as the CutOnce app, which weighs the pour beside the cubic yards and the bag count on one screen.
Updated
Weight is the pour volume times the mix density. Standard concrete is about 150 lb per cubic foot, so a cubic yard runs about 4,050 lb. Enter a slab or a volume you already have; the short tons help you check a truck or a trailer axle rating.
- short tons
- 2.50
- kg
- 2,268
- Volume
- 33.3 ft³
How the weight works
Concrete weight is the pour volume times the mix density. Standard concrete is about 150 pounds per cubic foot, so one cubic foot weighs 150 lb and a full cubic yard (27 cubic feet) weighs about 4,050 lb. Enter a slab and the calculator finds the volume first (length times width times thickness), then multiplies by the density of the mix you pick. Enter a volume you already have and it multiplies straight through.
A worked example
A 10 ft by 10 ft slab, 4 in thick, in standard concrete. Here is the volume, the weight three ways, and where each number comes from.
| Volume | 33.3 ft³ | 10 x 10 x 4 in / 12 |
| Weight | 5,000 lb | 33.3 ft³ x 150 lb/ft³ |
| Short tons | 2.50 | 5,000 lb / 2,000 |
| Kilograms | 2,268 | 5,000 lb x 0.4536 |
Mix density
The mix sets the density, and the density sets the weight. Standard ready-mix is the default; the others cover a reinforced pour, the two lightweight mixes, and a heavyweight shielding mix. These are the densities the calculator carries.
| Mix | lb/ft³ | kg/m³ |
|---|---|---|
| Standard | 150 | 2,403 |
| Reinforced | 156 | 2,499 |
| Lightweight structural | 115 | 1,842 |
| Lightweight insulating | 50 | 801 |
| Heavyweight | 300 | 4,806 |
When the weight matters
The weight decides how the pour gets handled. A truck or trailer has an axle rating, and wet concrete is heavy: a single cubic yard is over two short tons. A slab you are demolishing has to be broken and hauled, and the dumpster and the truck both have limits. A raised slab or a countertop puts its weight on the framing below, so the deck or the cabinets have to carry it. Weighing the pour up front keeps all of those inside their limits.
What the app adds
This page weighs the concrete. The app weighs it next to the pour itself: the volume in cubic yards, the bag count by bag size, the ready-mix threshold, and the metric mix inputs, all on one screen. It prints the result as a material list you take to the yard.
Common questions
- How much does a yard of concrete weigh?
- About 4,050 lb for standard concrete, a little over two short tons. A cubic yard is 27 cubic feet and standard concrete is about 150 lb per cubic foot, so 27 times 150 is 4,050 lb. A reinforced mix with the steel counted runs a bit heavier at about 4,212 lb; a structural lightweight mix drops to about 3,105 lb.
- How much does a concrete slab weigh?
- Figure the volume, then multiply by the density. A 10 ft by 10 ft slab 4 in thick is 33.3 cubic feet, and at 150 lb per cubic foot that is 5,000 lb, or 2.5 short tons. Double the thickness to 8 in and the weight doubles to 10,000 lb. The calculator does the volume and the multiply from the dimensions you enter.
- How much does a cubic foot of concrete weigh?
- About 150 lb for standard concrete. That is the density the whole estimate rests on: every other figure is that number times the volume. A reinforced mix is about 156 lb per cubic foot, a structural lightweight mix about 115, and a heavyweight shielding mix about 300.
- Does the weight include rebar?
- The reinforced mix option carries a slightly higher density (about 156 lb per cubic foot) to account for the steel spread through the pour. For the steel by itself, lay out the bars on the rebar calculator, which gives the total feet and the weight per bar size. The standard density is the plain concrete without added steel.
- Why weigh concrete at all?
- To keep it inside a limit: the axle rating of the truck or trailer that hauls it, the capacity of the dumpster a demolished slab goes into, or the load the framing under a raised slab has to carry. Wet concrete is heavier than it looks, so the weight is worth checking before the pour or the teardown, not after.
Weigh the pour, size the load
CutOnce weighs the concrete like this page, then adds the volume in cubic yards, the bag count, and the ready-mix threshold, all on one pour screen on the jobsite.
Free to download, with a 7-day trial of everything. This page weighs the pour; the app prints the material list for the concrete and the weight together.
See also