Calculate package length plus girth from length and girth or box dimensions, and compare the result with USPS, UPS, or FedEx size limits.
Length + Girth Formula
The basic length plus girth calculation adds the package length to its girth.
LG = L + G
- LG = length plus girth
- L = length
- G = girth
If you know the combined length plus girth and one other value, the missing value is found by subtraction.
L = LG - G
G = LG - L
For a box, length is the longest side. Girth is the distance around the two shorter sides.
G = 2(W + H)
LG = L + 2(W + H)
- L = longest side of the box
- W = one shorter side
- H = the other shorter side
- G = girth
- LG = length plus girth
The length plus girth tab lets you enter any two values and solve for the missing one. The box dimensions tab finds the longest side, calculates girth from the two shorter sides, then adds them together. Unit selections are converted internally so you can work in inches, feet, centimeters, or meters.
Common Length Plus Girth Limits
Package carriers often use length plus girth to decide whether a package is within size limits. Always check the exact service rules before shipping.
| Carrier or service | Common maximum length + girth | Notes |
|---|---|---|
| USPS, many domestic services | 108 in | Used for many standard mail classes. |
| USPS Ground Advantage | 130 in | Often allows larger packages than the 108 in limit. |
| UPS | 165 in | Large-package charges may still apply. |
| FedEx Ground and Express | 165 in | Oversize handling rules can vary by service. |
Length and Girth Unit Conversions
| Unit | Equivalent in inches | Equivalent in centimeters |
|---|---|---|
| 1 inch | 1 in | 2.54 cm |
| 1 foot | 12 in | 30.48 cm |
| 1 centimeter | 0.393701 in | 1 cm |
| 1 meter | 39.3701 in | 100 cm |
Examples
Example 1: Find length plus girth
You have a package with a length of 40 in and a girth of 60 in.
LG = 40 + 60 = 100\text{ in}The length plus girth is 100 in.
Example 2: Find length plus girth from box dimensions
A box measures 36 in by 14 in by 10 in. The longest side is 36 in, so the two shorter sides are 14 in and 10 in.
G = 2(14 + 10) = 48\text{ in}LG = 36 + 48 = 84\text{ in}The girth is 48 in, and the length plus girth is 84 in.
FAQs
What is girth on a package?
Girth is the distance around the thickest part of the package, not including the longest side. For a rectangular box, girth is twice the width plus twice the height, using the two sides that are not the longest side.
Which side counts as length?
The length is the longest side of the package. If you enter box dimensions, the longest of the three measurements should be treated as length, even if the box label calls a different side the length.
Is length plus girth the same as total dimensions?
No. Total dimensions usually means length plus width plus height. Length plus girth means the longest side plus the distance around the two shorter sides. For a box, that is length plus 2 times width plus 2 times height.
