Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Calculate concrete volume for a curb or curb-and-gutter run from its cross-section profile and run length.
Curbs -- along a driveway edge, a parking lot, or a landscaping bed -- are a long, continuous concrete extrusion with a fixed cross-section running the length of the curb. This calculator approximates that cross-section as a simple rectangle (height x face width) and multiplies it by the run length, the same "cross-section x length" logic used for a wall, applied at curb scale.
Enter the total curb run length in feet, then its cross-section profile: height and face width in inches. A common standard curb-and-gutter profile is roughly 6 inches tall by 18 inches wide, but landscaping curbs, parking-lot curbs, and DOT road curbs all use different standard profiles -- check your project's actual spec.
Volume (cu ft) = Length (ft) × Height (in÷12) × Width (in÷12)
This is useful for driveway edge curbing, parking lot curb-and-gutter runs, and landscape border curbing -- anywhere a continuous concrete edge is being formed and poured. If you're paving the driveway itself rather than just its edge curb, see the Driveway Calculator or Asphalt Calculator.
Real curb-and-gutter profiles are rarely a perfect rectangle -- most have a sloped face, a rounded top edge, or an integral gutter pan. Treating the profile as a rectangle slightly overestimates material for a curb with a sloped or rounded face, which is a safe direction to be wrong in for ordering purposes, but isn't an exact match to the true cross-sectional area.
A garden bed edging run measures 80 ft and is planned as a curb 8 in tall and 12 in wide. The volume is 80 × 0.667 × 1.0 = about 53.3 cubic feet. With a 10 percent allowance that becomes roughly 58.7 cubic feet, or about 2.17 cubic yards. Because that is a small load, you might compare renting a mixer and bagged concrete against a delivery from a supplier who may have a minimum order size.
80 × (8 ÷ 12) × (12 ÷ 12) = 53.3 cu ft
The tool multiplies height by width and by length, which treats the curb as a plain rectangular block. Real curbs often have a sloped face, a rounded top or a gutter pan. If your curb is roughly triangular or trapezoidal, the true area is smaller than the rectangle, so the calculated volume overshoots. For ordering that is the safer error, but if you are working to a tight budget you can compute the actual cross-sectional area from a drawing and multiply it by the length instead.
Tight curves and corner radii do not change the total length by much, but driveway aprons, drop sections for driveways and transitions may use different profiles from the standard run. Calculate those parts separately when you know their dimensions.
Curbs along public roads or connected to drainage systems often have specifications set by the local authority. Confirm the required profile and any inspection steps with the responsible department before pouring, because non-compliant work can be ordered removed.
Profiles vary by municipality and project type, but a 6-inch reveal (height) with an 18 to 24-inch total width (including the gutter pan) is common for residential and light commercial work -- always check your project's actual specification.
Yes, as long as you measure the total curved run length in feet along the curb's centerline -- the calculation doesn't care whether the run is straight or curved, only its total length.
Because real curb profiles are usually not a perfect rectangle (sloped faces, rounded edges, integral gutters reduce the true cross-sectional area versus a bounding rectangle) -- treat this as a conservative (slightly high) estimate rather than an exact figure.
Only if you include it in the width you enter. It treats the profile as a rectangle, so add the pan width and use the overall height.
The default allowance is a starting point. Rough grading, form bowing and spillage all use extra concrete, so ask your supplier what margin is appropriate for your site.
Convert first. Length goes in feet and the profile in inches, so multiply metres by 3.281 and centimetres by 0.3937 before entering.
It is the volume of finished concrete. Ask your supplier to convert that into the quantity of ready-mix to order.