Concrete Curb Calculator
Short answer: a 50 ft long, 6 × 6 inch curb needs 0.46 cubic yards — about 23 × 80 lb bags with 10% waste. Enter your curb below.
Calculate your curb
How the calculation works
A straight curb is a rectangular prism: volume = length × height × width, with length in feet and height and width in inches divided by 12, then divide cubic feet by 27 for cubic yards.
Worked example: a 50 ft curb, 6 in high and 6 in wide = 50 × 0.5 × 0.5 = 12.5 cu ft = 0.46 cubic yards net. With 10% waste: 0.51 cubic yards, about 23 × 80 lb bags.
Common curb sizes (per 10 ft run, net)
| Curb size | Volume | 80 lb bags |
|---|---|---|
| 6 × 6 in | 0.09 cubic yards | 5 |
| 6 × 8 in | 0.12 cubic yards | 6 |
| 8 × 8 in | 0.16 cubic yards | 8 |
| 8 × 12 in | 0.25 cubic yards | 12 |
Volumes are net (before waste). Bag counts use the 0.60 cu ft yield per 80 lb bag, rounded up.
Frequently asked questions
How much concrete for a 50 ft curb?
A 6 × 6 inch curb, 50 ft long, needs 0.46 cubic yards net (0.51 with 10% waste), about 23 × 80 lb bags.
How do you calculate concrete for a curb?
Multiply length × height × width, with height and width in feet, for cubic feet, then divide by 27 for cubic yards. Add 10% for waste.
Does this calculator cover curb and gutter?
No. Curb-and-gutter profiles are shaped, not rectangular. Measure the profile's cross-section area and multiply by the length, or use the cubic yard calculator with that area times the length.