Length plus girth explained
"Length plus girth" shows up in almost every carrier's size rules, and it's easy to get wrong. It's simply a way of measuring how big a package is in one number.
The definitions
Length is the longest side of the package. Girth is the distance around the package's thickest part, measured at right angles to the length. For a box, that's the sum of all four sides around the middle.
An example
A box is 24 × 18 × 12 inches. Length is 24. Girth is 2 × 18 + 2 × 12 = 60. Length plus girth is 84 inches.
Turning the box doesn't change the answer: length is always the longest side, so the calculation is always the same.
Why carriers use it
One number captures both a package's length and bulk. It lets carriers set a single size limit and flag packages that won't fit through sorting equipment or need special handling.
Typical limits
| Carrier | Commonly published limit |
|---|---|
| UPS and FedEx (ground parcel) | 108 in max length, 165 in length plus girth |
| UPS and FedEx large package | Over 130 in length plus girth, or longest side over 96 in |
| USPS (most services) | 108 in length plus girth |
| USPS Ground Advantage | 130 in length plus girth |
These change from time to time and vary by service. Use them as a guide and check your carrier's current rules before shipping anything near a limit.
Surcharges before the limit
You can pay extra well before hitting a maximum. UPS and FedEx commonly apply additional handling charges when the longest side exceeds 48 inches or the second-longest exceeds 30 inches, and large-package surcharges from 130 inches length plus girth. These can cost more than the base rate.
How to reduce it
Because girth counts the two shorter sides twice, trimming width or height has double the effect of trimming length. A box that's a little longer but slimmer can have a lower length plus girth than a squat one. For long items like rods, rugs or posters, a narrow box or tube is usually best.