Concrete Weight Calculator

A concrete weight calculator returns the weight of a poured slab or footing in pounds and tons. It multiplies the volume, from length, width and thickness, by a density of 150 lb per cubic foot by default. The density input can be lowered for a lightweight mix or raised slightly for a heavily reinforced section.

Last reviewed September 2026Method & sources Report an error

Not to scale.

Volume

33.3 cu ft

Breakdown
Volume	33.3 cu ft
Volume	1.23 cu yd
Weight	5,000 lb
Weight	2.50 tons

How to Calculate Concrete Weight

Weight is simply Volume × Density. Length × Width × (Thickness ÷ 12) gives the volume in cubic feet, and multiplying by the concrete's density in pounds per cubic foot gives its weight. 150 lb per cubic foot (4,050 lb per cubic yard) is the widely used default for normal-weight concrete. NRMCA's own CIP 8 technical bulletin uses a measured batch density of 151.0 lb/cu ft in its worked example, right in line with that figure. Actual density varies with the specific mix and aggregate, roughly 140-155 lb/cu ft for normal-weight concrete. That's why density is an adjustable input here rather than a fixed constant. Lower it toward 100-115 lb/cu ft for a lightweight (expanded-aggregate) mix, or raise it slightly for a heavily reinforced section, since embedded steel adds a small amount of density on top of the plain-concrete figure.

Example: 10 ft × 10 ft slab, 4 inches thick

A 10 ft × 10 ft slab, 4 inches thick, at the default 150 lb/cu ft density: 1. Area: 10 × 10 = 100 sq ft 2. Thickness in feet: 4 ÷ 12 = 0.333 ft 3. Volume: 100 × 0.333 = 33.3 cubic feet (1.23 cubic yards) 4. Weight: 33.3 × 150 = 5,000 lb (2.50 tons) That's the weight of the slab itself once cured. It isn't the fresh, unhardened weight during the pour, which is close but not identical.

Concrete Weight: Compare Scenarios

Scenario	Volume	Volume	Weight	Weight
Small (8x8 ft shed pad, 4 in.)	21.3 cu ft	0.79 cu yd	3,200 lb	1.60 tons
Medium (10x10 ft patio, 4 in.)	33.3 cu ft	1.23 cu yd	5,000 lb	2.50 tons
Large (24x24 ft garage slab, 5 in.)	240 cu ft	8.89 cu yd	36,000 lb	18.00 tons

What Is Concrete Weight?

A concrete weight calculator converts a slab or footing's dimensions into its total weight, in pounds and tons. It's used for planning things volume alone doesn't answer. Those include how much a load of demolished concrete will weigh for disposal or hauling. They also include whether a delivery truck or trailer is rated to carry it, and a rough check on soil bearing before involving an engineer for anything load-bearing.

Concrete Weight: Pros and Cons

Pros

Uses an adjustable density input grounded in NRMCA's own published batch data, rather than a single hardcoded number that ignores mix variation
Covers the lightweight-to-normal-weight concrete range in one field instead of a fixed assumption
Gives both pounds and tons, matching how disposal fees and hauling capacities are typically quoted

Cons

Not a substitute for an engineer's dead-load calculation on anything load-bearing or elevated. This is a material-weight estimate, not a structural design tool
Assumes a uniform thickness across the whole area. A thickened edge or footing needs its volume calculated and added separately
Density is an estimate you can adjust, not a lab-measured figure for your specific mix. For a demolition or hauling job with a hard weight limit, weigh a sample load if possible

Concrete Weight: What a Pro Checks

Use the adjustable density input instead of assuming a flat 150 lb/cu ft for anything unusual. Lightweight (expanded-aggregate) concrete runs closer to 100-115 lb/cu ft, and a heavily reinforced section weighs a bit more than plain concrete.
Get an actual scale weight before trusting a load close to a truck or trailer's rated capacity. Broken or demolished concrete also has more voids than a solid pour, which changes how much fits by volume even though the material's density per solid cubic foot doesn't change.
Remember fresh, unhardened concrete weighs slightly more than the cured figure this calculator gives. NRMCA's CIP 8 notes hardened volume can run about 2% less than the freshly mixed state.

Frequently Asked Questions

How much does a cubic yard of concrete weigh?

About 4,050 lb (roughly 2 tons) at the commonly used normal-weight density of 150 lb per cubic foot (150 × 27 = 4,050). NRMCA's own CIP 8 technical bulletin measured a real batch at 151.0 lb/cu ft, right around that figure. Actual weight varies somewhat by mix and aggregate.

How much does a cubic foot of concrete weigh?

About 150 lb for normal-weight concrete, the standard estimating figure used industry-wide. Lightweight concrete (made with expanded shale, clay, or slate aggregate) runs lighter, roughly 100-115 lb/cu ft, which is why this calculator's density field is adjustable rather than fixed.

Does reinforced concrete weigh more than plain concrete?

Slightly. Embedded rebar or wire mesh adds a small amount of weight on top of the plain-concrete figure, though not enough to change a rough estimate meaningfully unless the section is very heavily reinforced. For a precise structural dead-load figure, an engineer's calculation will account for the actual reinforcement ratio.

Can I use this to check if a truck or trailer can haul my old concrete?

It gives a starting estimate, so treat it as approximate. Confirm your vehicle or trailer's actual rated payload capacity. If the load is close to that limit, get an actual scale weight rather than relying on an estimate. Broken or demolished concrete also has more voids than a solid pour, which affects how much fits by volume even though the material's density per solid cubic foot is unchanged.

Is fresh (wet) concrete a different weight than cured concrete?

They're close but not identical. Freshly mixed concrete is slightly heavier due to the water content before curing, and some minor volume loss from settlement and drying shrinkage happens as it hardens. NRMCA's CIP 8 notes hardened volume can run about 2% less than the freshly mixed state. This calculator's density figure applies to normal, already-cured concrete.

What density should I use for lightweight concrete?

Structural lightweight concrete (made with expanded shale, clay, or slate aggregate instead of normal stone) commonly runs around 100-115 lb/cu ft, versus roughly 140-155 lb/cu ft for normal weight. If you know the specific mix's tested unit weight, use that instead of a general range.

Sources

NRMCA CIP 8: Discrepancies in Yield (worked example measuring a real batch at 151.0 lb/cu ft density; ASTM C138 density test method) (opens in a new tab)

Concrete & Masonry