Concrete Curb Calculator Guide
Calculate concrete curb volume by linear feet, curb profile, gutter width, waste, cubic yards, 80 lb bags, ready-mix cost, and quote scope.
Quick answer
100 ft curb = 4.07 yd3
6x6 curb plus 18x6 gutter with 10% waste; separate material $/ft from installed scope
A concrete curb calculator turns linear feet and profile dimensions into cubic yards, bag count, ready-mix cost, and cost per linear foot. The profile matters: a curb-only pour, curb and gutter, rolled curb, and driveway apron edge can use very different concrete quantities even when the linear feet look similar.
Use the Concrete Curb Calculator for the interactive profile estimate. Use the Concrete Curb and Gutter Cost per Linear Foot Guide when comparing installed quotes, and use the Concrete Quote Reviewer when removal, forms, drainage, right-of-way, traffic control, or cleanup are bundled into the bid.
Quick answer
For a simple rectangular planning profile:
curb cross-section sq ft =
curb width in x curb height in / 144
For curb and gutter:
total cross-section sq ft =
curb cross-section sq ft
+ gutter width in x gutter thickness in / 144
Then:
curb cubic yards =
linear feet x total cross-section sq ft x (1 + waste percent) / 27
A 100 ft run with a 6 in by 6 in curb and an 18 in by 6 in gutter is about 3.70 yd3 before waste or 4.07 yd3 with 10% waste. At $165 per yd3 plus a $150 delivery or short-load placeholder, the material-only check is about $821.55, or $8.22 per linear ft before removal, forms, labor, traffic control, permits, finish, drainage, and cleanup.
Curb calculator inputs
| Input | Why it matters | Quote question |
|---|---|---|
| Linear feet | Multiplies concrete, forms, and finish length. | Are returns, radii, and tie-ins included? |
| Curb width | Controls curb cross-section. | What profile drawing or dimension is priced? |
| Curb height | Changes concrete and formwork. | Is height measured from gutter, pavement, or grade? |
| Gutter width | Adds material and drainage surface. | Is this curb-only or curb and gutter? |
| Gutter thickness | Changes cubic yards and finish timing. | What gutter slab thickness is included? |
| Waste factor | Adds cushion for profile loss and irregular tie-ins. | Is waste already included in the order quantity? |
| Ready-mix price | Sets material cost per linear foot. | Is delivery, short-load, fuel, tax, and wait time included? |
| Installed quote total | Lets you compare installed $/ft. | What scope explains the gap from material-only cost? |
Common curb examples
These examples include 10% waste and use a common 0.60 ft3 yield for 80 lb bags. They are planning checks only.
| Curb profile | Linear feet | With 10% waste | 80 lb bags |
|---|---|---|---|
| 6 in x 12 in vertical curb | 60 ft | 1.22 yd3 | 55 bags |
| 6 in x 6 in curb + 18 in x 6 in gutter | 100 ft | 4.07 yd3 | 184 bags |
| 8 in x 6 in curb + 24 in x 6 in apron edge | 24 ft | 1.30 yd3 | 59 bags |
| 6 in x 6 in curb-only run | 100 ft | 1.02 yd3 | 46 bags |
For small curb-only repairs, bags may be practical. For long curb and gutter runs, ready-mix usually deserves the first quote because bag count and finish timing rise quickly.
Material-only vs installed curb price
The calculator should separate two numbers:
material $/linear ft =
ready-mix concrete + delivery + fees
/ linear feet
installed $/linear ft =
contractor quote total
/ linear feet
Those numbers are not supposed to match. Installed curb work can include saw cutting, removal, excavation, forms, staking, finish, drainage correction, driveway transitions, traffic protection, public right-of-way rules, cleanup, and warranty.
Curb quote worksheet
| Quote line | Bid A | Bid B | Notes |
|---|---|---|---|
| Total linear feet | Include radii, returns, tie-ins, and transitions. | ||
| Profile dimensions | Curb height/width and gutter width/thickness. | ||
| Concrete quantity | Cubic yards, waste, delivery, short-load. | ||
| Removal | Saw cut, demo, load, haul-off, disposal. | ||
| Forms and finish | Form type, stakes, strip, edge, finish, cleanup. | ||
| Reinforcement or dowels | Rebar, dowels, mesh, or none. | ||
| Drainage and slope | Gutter line, low spots, inlets, driveway apron. | ||
| Permit or right-of-way | City approval, inspection, traffic control. | ||
| Access and washout | Truck reach, buggy, pump, staging, washout area. |
If a contractor quote only says "curb, 100 ft," ask for the profile, removal, forms, drainage, and permit responsibility before comparing price.
FAQ
How do I calculate concrete for a curb?
Calculate the curb profile cross-section in square feet, multiply by linear feet, add waste, then divide cubic feet by 27 to get cubic yards.
How many yards are in 100 ft of curb and gutter?
For a 6 in by 6 in curb plus an 18 in by 6 in gutter, 100 ft is about 3.70 yd3 before waste or 4.07 yd3 with 10% waste.
Can I use bags for curb concrete?
Small curb repairs may work with bags. Long curb and gutter runs usually need ready-mix because placement speed, finish timing, forms, and consistency matter.
Why does curb cost per foot exceed material cost?
Installed curb pricing can include removal, excavation, forms, finish labor, drainage correction, traffic control, permits, cleanup, and contractor overhead. Concrete material is only one line.
Does this replace permit or right-of-way review?
No. Public curb, gutter, apron, and sidewalk tie-in work may require local approval, inspection, traffic protection, and specific profiles.
Next step
Run the profile in the Concrete Curb Calculator. Then compare the full linear-foot scope, not just the concrete yards.
Quote planning next step
Turn this guide into a concrete buying check
Run the matching calculator, then compare ready-mix, bagged concrete, delivery fees, access needs, and quote gaps before you buy materials or approve a contractor number.