What girth measures
Girth is the distance around the package perpendicular to its longest side. For a rectangular carton it is two times width plus two times height.
Length plus girth adds the longest side to that perimeter. Carriers can use the combined number to identify parcels that are awkward for automated networks even if their scale weight is modest.
Example
For a parcel 48 inches long, 20 inches wide and 16 inches high, girth is 2 × 20 + 2 × 16 = 72 inches. Length plus girth is therefore 120 inches.
Use the widest external points and the carrier's required rounding method. Deformed cartons or protruding packaging can make the measured package larger than its printed box specification.
Check the current service limit
Cargoivo calculates the geometry but does not enforce one universal carrier maximum. Limits and surcharges vary by service, destination and date.
Always compare the result with current carrier documentation before shipping a parcel close to an oversize threshold.
Calculate the margin against a stated limit
Use a hypothetical length-plus-girth limit of 120 inches, not a universal carrier limit. The 48 × 20 × 16 inch box is exactly 120 inches, leaving no margin. Increasing its width to 20.5 inches makes the unrounded result 121 inches; if a service rounds that width up to 21, the rated result becomes 122 inches.
Reducing the longest side by 1 inch reduces the combined measure by 1 inch. Reducing either smaller side by 1 inch reduces it by 2 inches, provided the side ordering stays the same. The calculator now identifies the longest entered side automatically; it does not apply service-specific dimension rounding.
Reproduce the calculation
Use the related Cargoivo calculator with your own shipment dimensions, weight, or quantity.
Open Package Girth Calculator →Cargoivo provides educational planning information, not a freight quote, engineering approval, customs advice, or carrier commitment. Verify current service rules, equipment specifications, and commercial terms before shipping.