Length and girth calculator
Enter the box. You get its length, girth and length plus girth, and whether USPS, UPS and FedEx will take it as it is, charge a surcharge for its size, or refuse it.
Inputs
Result
What each carrier does with this box
Size and weight thresholds only. Fees change every January and July, and some apply at a contract rate; check the amount with your carrier.
| Carrier | Result | Why |
|---|
How to calculate length and girth
Measure all three sides, call the longest one the length whichever way the box will travel, and wrap a tape around the other two. A 30 × 20 × 10 in box has a girth of 2 × 20 + 2 × 10 = 60 in and a length plus girth of 30 + 60 = 90 in. UPS gives the same formula: “2x Width + 2x Height”. Round each side up to the next whole inch first; carriers measure that way, and a box at 29.2 in is a 30 in box to them.
Size limits by carrier
| Carrier and service | Max weight | Max length + girth | Size surcharges |
|---|---|---|---|
| USPS Priority Mail, Priority Mail Express | 70 lb | 108 in | Nonstandard fees for length over 22 in, over 30 in, and volume over 2 cubic feet (3,456 cu in) |
| USPS Ground Advantage | 70 lb | 130 in | Oversized price, by zone and regardless of weight, over 108 in up to 130; the same nonstandard fees |
| UPS | 150 lb | 165 in, length 108 in | Additional Handling: longest side over 48 in, second-longest over 30 in, over 10,368 cu in or over 50 lb. Large Package: length + girth over 130 in, length over 96 in, over 17,280 cu in or over 110 lb |
| FedEx | 150 lb | 165 in, length 108 in | Additional Handling: as UPS, plus length + girth over 105 in. Oversize: length + girth over 130 in, length over 96 in, over 17,280 cu in or over 110 lb |
USPS: Quick Service Guides 220 (Priority Mail) and 280 (Ground Advantage), Notice 123. UPS: “Shipping dimensions and weight” and “Avoid additional shipping fees” on ups.com (February 2026). FedEx: Service Guide thresholds, including the cubic-size triggers added 12 January 2026, as summarised in Sifted’s 2026 surcharge guide; we could not load fedex.com to check them directly. A package over the large-package line is charged that instead of Additional Handling, not both.
The biggest box each limit allows
Length plus girth punishes cubes least and long, thin boxes most. The largest cube under each limit is a fifth of the limit on every side, because a cube’s length plus girth is five times its side:
| Limit | Largest cube | What it is |
|---|---|---|
| 105 in | 21 in | FedEx Additional Handling starts above this |
| 108 in | 21 in | USPS Priority Mail maximum; Ground Advantage oversized price above it |
| 130 in | 26 in | USPS Ground Advantage maximum; UPS Large Package and FedEx Oversize above it |
| 165 in | 33 in | UPS and FedEx maximum |
The cubic and side-length triggers often bite before length plus girth does. A 24 in cube is only 120 in of length plus girth, but it is 13,824 cu in, over the 10,368 cu in Additional Handling line at UPS and FedEx. Long items catch the 48 in rule first: a 49 × 12 × 10 in box is only 93 in of length plus girth, but its longest side is over 48 in.
Three boxes, three answers
| Carrier | Result | Why |
|---|---|---|
| 40 × 32 × 10 in, 10 lb — length + girth 124 in | ||
| USPS Priority Mail and Priority Mail Express | Not accepted | length and girth 124 in, over 108 |
| USPS Ground Advantage | Surcharge: Oversized price, length and girth over 108 in, Nonstandard fee, length over 30 in, Nonstandard fee, over 2 cubic feet | length and girth 124 in, over 108; length 40 in, over 30; 12,800 cu in, over 3,456 |
| UPS Ground and air | Surcharge: Additional Handling | second-longest side 32 in, over 30; 12,800 cu in, over 10,368 |
| FedEx Ground and Express | Surcharge: Additional Handling | second-longest side 32 in, over 30; length and girth 124 in, over 105; 12,800 cu in, over 10,368 |
| 60 × 20 × 20 in, 30 lb — length + girth 140 in | ||
| USPS Priority Mail and Priority Mail Express | Not accepted | length and girth 140 in, over 108 |
| USPS Ground Advantage | Not accepted | length and girth 140 in, over 130 |
| UPS Ground and air | Surcharge: Large Package Surcharge | length and girth 140 in, over 130; 24,000 cu in, over 17,280 |
| FedEx Ground and Express | Surcharge: Oversize charge | length and girth 140 in, over 130; 24,000 cu in, over 17,280 |
Questions
How do you calculate length and girth?
Take the longest side as the length. Girth is twice the width plus twice the height, the distance around the box at its thickest point. Add them: length + 2 × width + 2 × height. A 30 × 20 × 10 in box has a girth of 60 in and a length plus girth of 90 in.
What is the maximum length and girth for USPS?
108 inches combined for Priority Mail and Priority Mail Express, and 130 inches for USPS Ground Advantage, where anything over 108 inches pays the oversized price for its zone whatever it weighs. The weight limit is 70 lb for all three.
What is the UPS maximum length and girth?
165 inches of length plus girth, 108 inches of length and 150 lb. Over any of those, UPS charges an Over Maximum Limits charge. Over 130 inches of length plus girth, or 96 inches of length, a Large Package Surcharge applies.
What is the FedEx maximum size?
165 inches of length plus girth, 108 inches of length and 150 lb. FedEx charges an oversize charge above 130 inches of length plus girth or 96 inches of length, and Additional Handling above 105 inches of length plus girth, 48 inches on the longest side or 30 inches on the second-longest.
Is girth the same as width?
No. Girth is the distance all the way around the package: two widths and two heights. A box 20 inches wide and 10 inches high has a girth of 60 inches.
Does length plus girth include height?
Yes, twice over. Height is half of the girth along with width. Only the longest side, the length, is counted once.
What is the biggest box I can send with USPS?
A box whose length plus girth is up to 130 inches by USPS Ground Advantage, or 108 inches by Priority Mail. The largest cube is 26 inches a side for Ground Advantage and 21 inches for Priority Mail. Over 22 inches long, 30 inches long or 2 cubic feet, nonstandard fees apply.
How do you measure girth on a round or odd-shaped package?
Measure around the thickest part with a tape. For postage and surcharges, carriers generally measure the smallest box that would enclose the item, so a tube is measured as a square box of its diameter.