Linear materials calculator · curb / kerb v1.0
Concrete Curb / Kerb Calculator
Calculate how much concrete you need for a curb or kerb from measured run length and cross-section, then keep contingency, order quantity and cost separate.
✓No signup
✓US + metric
✓Precast + cast-in-place
✓Editable support assumptions
Cast-in-place curb example
Concrete curb cubic yards per linear foot
For a rectangular or equivalent average section: length (ft) × width (in) × height (in) ÷ 144 ÷ 27 = yd³. Curb is the primary US term; kerb is retained as a secondary international synonym.
- Volume per linear foot
- 0.167 ft³ 4 × 6 in rectangular section
- Raw for 100 ft
- 0.62 yd³ 16.67 ft³ before contingency
- With 10% contingency
- 0.68 yd³ Before supplier rounding
- 80-lb bag order
- 31 bags Verified 0.60-ft³ yield
Assumptions in this example
- 100-linear-ft run.
- 4 × 6 in rectangular cast-in-place cross-section.
- 10% example contingency and 0.25-yd³ ready-mix order increment.
The rounded ready-mix example is 0.75 yd³. These dimensions are quantity examples, not a design recommendation.
Step 1
Enter the curb / kerb run
For precast work, bedding and haunch dimensions are editable planning inputs — use your project detail where known.
Ordering & pricing
Advanced assumptions
The 100-ft, 4 × 6-in example in separate stages
- Raw volume
- 0.62 yd³ 16.67 ft³ geometric volume
- Contingency
- 0.68 yd³ After the explicit 10% example contingency
- Rounded order
- 0.75 yd³ Rounded to the existing 0.25-yd³ example increment
- Bag quantity
- 31 bags 80-lb product at 0.60 ft³ per bag
Cast-in-place curb quantities by cross-section and run
These are rectangular/equivalent-section quantity examples. For a shaped profile, use dimensions that transparently represent its equivalent average cross-sectional area.
| Volume | Whole bags with 10% | Order | ||||||
|---|---|---|---|---|---|---|---|---|
| Example section | Run | ft³ / linear ft | Raw yd³ | yd³ + 10% | 40 lb | 60 lb | 80 lb | Rounded yd³ |
| 4 × 4 in | 25 ft | 0.111 | 0.10 | 0.11 | 11 | 7 | 6 | 0.25 |
| 4 × 4 in | 50 ft | 0.111 | 0.21 | 0.23 | 21 | 14 | 11 | 0.25 |
| 4 × 4 in | 100 ft | 0.111 | 0.41 | 0.45 | 41 | 28 | 21 | 0.50 |
| 4 × 4 in | 200 ft | 0.111 | 0.82 | 0.91 | 82 | 55 | 41 | 1.00 |
| 4 × 6 in | 25 ft | 0.167 | 0.15 | 0.17 | 16 | 11 | 8 | 0.25 |
| 4 × 6 in | 50 ft | 0.167 | 0.31 | 0.34 | 31 | 21 | 16 | 0.50 |
| 4 × 6 in | 100 ft | 0.167 | 0.62 | 0.68 | 62 | 41 | 31 | 0.75 |
| 4 × 6 in | 200 ft | 0.167 | 1.23 | 1.36 | 123 | 82 | 62 | 1.50 |
| 6 × 6 in | 25 ft | 0.250 | 0.23 | 0.25 | 23 | 16 | 12 | 0.50 |
| 6 × 6 in | 50 ft | 0.250 | 0.46 | 0.51 | 46 | 31 | 23 | 0.75 |
| 6 × 6 in | 100 ft | 0.250 | 0.93 | 1.02 | 92 | 62 | 46 | 1.25 |
| 6 × 6 in | 200 ft | 0.250 | 1.85 | 2.04 | 184 | 123 | 92 | 2.25 |
| 6 × 8 in | 25 ft | 0.333 | 0.31 | 0.34 | 31 | 21 | 16 | 0.50 |
| 6 × 8 in | 50 ft | 0.333 | 0.62 | 0.68 | 62 | 41 | 31 | 0.75 |
| 6 × 8 in | 100 ft | 0.333 | 1.23 | 1.36 | 123 | 82 | 62 | 1.50 |
| 6 × 8 in | 200 ft | 0.333 | 2.47 | 2.72 | 245 | 163 | 123 | 2.75 |
Concrete curb quantity questions
How many cubic yards are in 100 linear feet of concrete curb?
It depends on the cross-section. The 4 × 6 in rectangular example above is about 0.62 yd³ raw, before the separately shown contingency and order rounding.
How do I calculate a curved curb run?
Measure the centerline or other specified reference line of the actual curve, then enter that total run length. The volume calculation uses the measured run.
How do I estimate a sloped or shaped curb section?
Use an equivalent average width and height only when they accurately represent the project cross-sectional area. Do not treat a bounding rectangle as the shaped profile.
When do bags stop being practical versus ready mix?
That is a project and supplier decision. The calculator displays whole bags and a separately rounded ready-mix quantity so you can compare logistics and current quotes.
Does the calculator design the curb or reinforcement?
No. It estimates material from a supplied run and section. Curb shape, support, reinforcement, joints, and strength come from the project detail.
Can it calculate curb and gutter?
Not as a dedicated composite profile. Only use the cast controls if an equivalent average section has been established transparently from the project detail.
Sources and calculation basis
- QUIKRETE Concrete Mix Data Sheet 1101 — verified bag yields.
- JobsiteMeasure methodology and source register — geometry, contingency, and procurement-rounding basis.
Values generated September 3, 2026.