Curb and Gutter Calculator
Cubic yards and bags of concrete for a curb-and-gutter run — from the section dimensions and length.
order +10% = 2.5 cu yd · bags = 115
A curb-and-gutter run is a long prism: the same cross-section repeated for the whole length. That cross-section is two rectangles — the vertical curb (its height times its width) sitting on the back edge of the flat gutter pan (the pan's width times its depth). Add those two rectangle areas together and you have the composite cross-section; multiply by the run length and you have the concrete volume. Modeling the section as a sum of rectangles is how DOT curb-and-gutter quantities are estimated.
The calculator works in SI internally, so it converts your inches and feet to meters, computes the area and volume exactly, then adds a waste allowance for subgrade that is never perfectly graded, forms that flex, and the concrete left in the chute. It converts the padded volume to cubic yards for ordering ready-mix and also divides by bag yield — about 0.60 cubic feet per 80 lb bag — for the bagged route, always rounding bags up.
Most curb runs cross the point where bags stop making sense. Past roughly 1.5 cubic yards the tool flags that a ready-mix truck is usually cheaper and pours the run continuously, which matters for a curb where cold joints are both ugly and weak.
section = (6 × 6) + (24 × 6) = 180 in² = 1.25 ft²
volume = 1.25 × 50 = 62.5 cu ft → +10% = 68.75 cu ft = 2.5 cu yd = 1.95 m³
80 lb bags = ceil(68.75 ÷ 0.60) = 115