Concrete Curb Calculator
Estimate concrete volume, bag quantity, formed surface, placed weight and cost for straight concrete curbs.
Default project preview
0.68 yd³
Concrete bags
31
Base volume
0.62 yd³
Total curb length
50 ft
Formed surface
91.7 ft²
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Curb length
Enter this project assumption in ft. The current imperial default is 50 ft.
Curb width
Enter this project assumption in in. The current imperial default is 6 in.
Curb height
Enter this project assumption in in. The current imperial default is 8 in.
Equal curb runs
Enter this project assumption in a unitless value. The current imperial default is 1. Minimum: 1.
Extra allowance
Enter this project assumption in %. The current imperial default is 10 %. Minimum: 0. Maximum: 50.
Concrete yield per bag
Enter this project assumption in ft³. The current imperial default is 0.6 ft³.
Ready-mix price
Enter this project assumption in per yd³. The current imperial default is 165 per yd³. Minimum: 0.
Price per bag
Enter this project assumption in a unitless value. The current imperial default is 7. Minimum: 0.
How to read the outputs
Concrete bags
rounded full bags. Default preview: 31.
Base volume
before allowance. Default preview: 0.62 yd³.
Total curb length
all equal runs. Default preview: 50 ft.
Formed surface
top and two sides. Default preview: 91.7 ft².
Placed weight
planning density. Default preview: 2,747 lb.
Cost comparison
ready-mix / bags. Default preview: $112.04 / $217.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Volume = curb length × width × height × quantity. The allowance is applied, then concrete bags are rounded up from the entered bag yield.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: July 30, 2026
Use this calculator to estimate concrete for a straight curb from length and cross-sectional dimensions, including an optional gutter or thickened portion. It does not determine curb profile, reinforcement or roadway design.
Calculation steps
- 1Define the curb cross-sectional area.
- 2Add any integral gutter or thickened section area.
- 3Multiply total cross-section by curb length.
- 4Apply allowance and convert to the supplier unit.
Worked numerical example
A curb 100 ft long with a 6 in × 12 in rectangular section has 50 ft³ of concrete, or 1.85 yd³. With 10% allowance, plan approximately 2.04 yd³.
Purchasing and rounding
Ready-mix is ordered by cubic yard or cubic metre increments. Continuous curb placement may require allowance for machine or form residual material.
Interpret the result
The cross-section controls volume directly. Small profile changes over long runs can materially change the order.
Page-specific assumptions
- Uniform curb profile.
- Straight measured centerline length.
- No separate footings unless entered.
- Openings and transitions are calculated separately.
Common mistakes
- Using curb face area instead of cross-section.
- Ignoring integral gutter volume.
- Mixing inches and feet.
- Applying one profile to transitions.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
FAQ
Concrete Curb Calculator questions
How much extra concrete should a curb order include?+
A modest allowance helps cover uneven base, form variation and spillage. Confirm larger pours with the supplier.
Does the calculator design the curb?+
No. Dimensions, reinforcement, joints and base preparation require a project-specific design.
Why is formed surface shown?+
It helps estimate form contact area for the top and two exposed sides of a simple rectangular curb.