Parcel size, girth & carrier limit checker
Calculate package girth and length plus girth in inches or centimetres, then check recorded UPS and USPS limits using your packed dimensions and weight.
3 of 3 services are within the limits recorded here. This is not acceptance or a surcharge quote.
The longest side is length, regardless of which box you entered it in. Girth uses the other two sides. Weight is needed only for the service-limit check.
| Step | Working | Result |
|---|---|---|
| Longest side (treated as length)Carriers always measure the longest side as the length, whatever order you enter. | 60 cm | |
| GirthGirth is the distance around the parcel at its thickest point. | 2 × (40 + 30) | 140 cm |
| Length + girth | 60 + 140 | 200 cm |
| Carrier | Service limits | Result |
|---|---|---|
| UPS US daily rates | Package limits | Within listed limits |
| USPS | Most services | Within listed limits |
| USPS | USPS Ground Advantage | Within listed limits |
Limits are per piece and are the published maximums for standard parcel services. Contract terms, freight services and specific lanes can differ — this is a first check, not an acceptance guarantee.
Measure the packed box, then identify the longest side
Enter the outside dimensions, including bulges or protrusions. The calculator sorts the sides: the longest is length; the other two are width and height. Girth is the distance around those two shorter sides: 2 × (width + height). Length plus girth adds the longest side. Rotating the same rectangular box does not change this result.
Worked examples in inches and centimetres
A 20 × 12 × 8 inch box has a girth of 2 × (12 + 8) = 40 inches and length plus girth of 60 inches. In metric, a 60 × 40 × 30 cm carton has 140 cm girth and 200 cm length plus girth. Select the matching unit before entering dimensions. Weight is not needed for the geometry, but is required for the service-limit comparison.
Geometry is not a billable measurement
The girth result uses the measurements you enter. The comparison converts them to centimetres without applying a universal carrier rounding rule. UPS guidance rounds dimensions up to whole units; check the service rule and use its rounded measurements before relying on a near-limit result. For example, 20.1 × 12.1 × 8.1 inches gives 60.5 inches as measured, but 21 × 13 × 9 gives 65 inches after rounding each side up.
How to read the service comparison
Within listed limits means only that the recorded size and weight tests passed. It does not establish acceptance or a surcharge-free price. Packaging shape, material, service, route and account terms can introduce other restrictions. An oversize result identifies a recorded size band; an exceeds-limits result identifies which recorded maximum was crossed. Confirm the current tariff before buying a label.
Compare a repacking option
Keeping the longest side unchanged, reducing either shorter side by one inch reduces girth by two inches. That only helps if the product and protection still fit. Compare chargeable weight in the dimensional-weight calculator, then price each parcel in the shipping-cost worksheet. Splitting a box can change both billed weight and per-piece fees; it does not guarantee a saving.
Questions people ask about this
Answers written from the published rules, not from other people's summaries of them. Every figure quoted below is listed with its source at the foot of this page.
Every formula on this siteHow do I calculate package girth?
Use twice the sum of the two shorter dimensions. A 20 by 12 by 8 inch box has 40 inches of girth. Add its 20-inch longest side for 60 inches of length plus girth.
Can I calculate girth without knowing the weight?
Yes. Positive dimensions are enough for girth. Enter the packed weight when you also want to compare the recorded carrier service limits.
Why can a parcel within these limits still receive a surcharge?
The tool checks recorded size and weight limits, not every billing rule. Packaging, shape, individual side thresholds and account terms may produce additional charges. Use the current service tariff for the price.
Is girth the same as dimensional weight?
No. Girth is a distance around the parcel. Dimensional weight divides its volume by a service-specific divisor and is compared with actual weight to determine billed weight.
Do these formulas cover cylinders or irregular parcels?
The calculator treats the dimensions as a rectangular box. Follow the chosen carrier measurement instructions for irregular shapes and check any packaging-specific charges separately.
Further reading
Related calculators
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Where these numbers come from
Rates and rules change, and a calculator running on stale data is worse than no calculator. Every figure below carries the date we last checked it and a confidence level, so you can judge how much weight to put on it.
| Source | Publisher | Effective | Confidence |
|---|---|---|---|
| Parcel size, weight and fee standards Combined length and girth: 108 inches maximum for most services, 130 inches for USPS Ground Advantage. Between 108 and 130 inches the parcel is priced as oversize. | USPS | Not specifiedChecked 2026-08-17 | Primary source |
| UPS US dimensions, billable weight and size limits US daily divisor 139; retail divisor 166; whole-pound billing; 150 lb, 108 inch length and 165 inch combined limit. This page includes conflicting general measurement wording; the preset follows its explicit round-up instructions. Confirm the governing service guide or contract. | UPS | Not specifiedChecked 2026-09-21 | Primary source |
Page updated . Spotted something out of date? Tell us — corrections are published with the date they were made.
More on the working: every formula on this site, the full source register, what the terms mean, and how we decide what to publish. What an estimate here can and cannot support is set out in the accuracy notes.