Concrete weight calculator
How much concrete weighs: a yard, a cubic foot, a bucket, a slab or a column, in pounds, tons and kilograms.
It weighs about
3,915 lb
- Range
- 3,780–4,050 lb
- Tons
- 1.96 (short tons)
- Kilograms
- 1,776 kg (1.78 t)
- Volume
- 27.00 ft³ (1.00 yd³)
- Density used
- 145.0 lb/ft³
Normal-weight concrete is typically 140–150 lb per cubic foot (Iowa DOT) and structural lightweight 90–115 (ACI 318); for those, the weight uses the middle of the range. More entrained air makes concrete lighter. Steel reinforcement adds a little; the rebar calculator gives its weight.
How much does concrete weigh?
Weight is volume times density. Work out the volume in cubic feet, then multiply by the weight of a cubic foot of concrete.
- Slab: length × width × thickness ÷ 12 = cubic feet
- Round column: π × (diameter ÷ 12)² ÷ 4 × height = cubic feet
- Cubic yards × 27 = cubic feet; gallons × 231 ÷ 1,728 = cubic feet
- Weight = cubic feet × 145 lb (normal weight) or 102.5 lb (lightweight)
Worked example
A cubic yard is 27 cubic feet, so it weighs 27 × 145 = 3,915 lb, about 1.96 tons, anywhere from 3,780 to 4,050 lb across the normal range. A 10 × 10 ft slab 4 in. thick is 10 × 10 × 4 ÷ 12 = 33.33 ft³, or 4,833 lb.
Concrete weight per cubic yard
Normal weight from Iowa DOT Materials IM 340, Weight per Cubic Foot, Yield & Air Content (Gravimetric) of Concrete; lightweight is structural lightweight concrete as ACI 318 defines it, from NRMCA Concrete in Practice, TIP 9, Density of Structural Lightweight Concrete (citing ACI 318).
| Volume | Normal weight | Tons | Lightweight |
|---|---|---|---|
| 1 ft³ | 145 lb | 0.072 | 102.5 lb |
| 1 yd³ | 3,915 lb | 1.96 | 2,768 lb |
| 2 yd³ | 7,830 lb | 3.92 | 5,535 lb |
| 3 yd³ | 11,745 lb | 5.87 | 8,302 lb |
| 5 yd³ | 19,575 lb | 9.79 | 13,838 lb |
| 8 yd³ | 31,320 lb | 15.66 | 22,140 lb |
| 10 yd³ | 39,150 lb | 19.57 | 27,675 lb |
Slab weight per square foot
Normal-weight concrete at 145 lb/ft³.
| Thickness | lb per sq ft | 100 sq ft |
|---|---|---|
| 4 in. | 48.3 | 4,833 lb |
| 5 in. | 60.4 | 6,042 lb |
| 6 in. | 72.5 | 7,250 lb |
| 8 in. | 96.7 | 9,667 lb |
Concrete weight questions
How much does a yard of concrete weigh?
About 3,915 lb, or 1.96 tons: a cubic yard is 27 cubic feet at about 145 lb each. Normal-weight concrete runs 140–150 lb per cubic foot, so a yard is 3,780–4,050 lb. Lightweight concrete is about 2,768 lb a yard.
How much does a cubic foot of concrete weigh?
About 145 lb, within 140–150 lb for normal-weight concrete. That figure is the concrete's unit weight; concrete crews measure it on fresh concrete to check the air content and yield of a batch.
What is the unit weight of concrete?
140 to 150 lb/ft³ for normal-weight concrete at 5 to 8 percent air, per Iowa DOT, and 90 to 115 lb/ft³ for structural lightweight concrete as ACI 318 defines it. In metric, 145 lb/ft³ is about 2,323 kg/m³.
How much does a 5 gallon bucket of concrete weigh?
A full 5 gallon bucket holds 0.67 ft³, so it weighs about 97 lb of wet concrete.
How much does a concrete slab weigh?
A 4 in. slab weighs about 48.3 lb per square foot, so a 10 × 10 ft slab is about 4,833 lb (2.42 tons). Choose "Slab" above for any size; the table above has other thicknesses.
How much does a bag of concrete weigh?
The weight is on the bag: QUIKRETE sells 80, 60, 50 and 40 lb bags. An 80 lb bag yields about 0.6 ft³ of concrete once mixed. The concrete calculator counts bags for a job.