Three numbers cover almost every trip you will take.
22 x 14 x 9 inches is the standard carry-on across most major US airlines. 62 linear inches, meaning the length, width, and depth added together, is the standard for a checked bag. A personal item is around 17 x 10 x 9 inches and goes under the seat in front of you.
Everything else is detail. The detail is where people get caught out, so here it is.
The Three Sizes
| Bag type | Typical US limit | In centimeters | Weight |
|---|---|---|---|
| Personal item | 17 x 10 x 9 in | 43 x 25 x 23 cm | Rarely weighed |
| Carry-on | 22 x 14 x 9 in | 56 x 36 x 23 cm | Rarely weighed on US domestic |
| Checked bag | 62 linear inches | 157 linear cm | 50 lb |
Personal item limits vary more than the other two, because airlines describe them loosely and enforce them by whether the bag actually fits under the seat.
What Kind of Traveler Are You?
There are six types of travelers; here’s what each one actually needs.
The Weekender
One or two nights. A city reset, a wellness weekend, somewhere you can drive to by dinner. A personal item does more than people expect at this length, and a small carry-on covers it with room to spare. The trip is short enough that the bag should never slow you down.
The City Traveler
Two to four days in a place you came for the food, the galleries, or the shopping. A carry-on, and one you are happy to be photographed with, because it is going to be beside you at a hotel desk and in the back of a cab more than it is going to be in a hold. Leave room for what you bring home.
The Carry-On Loyalist
You have not checked a bag in years and you are not starting now. You want the largest carry-on that is still legal, which means the measurement matters more to you than to anyone else on this list. Measure with the wheels and the handle included. That is how the gate measures.
The Family Organizer
You are packing for more than yourself, and probably for people who packed badly. One large checked bag plus a cabin bag each is the usual shape. Two sizes that nest inside each other are worth more here than anywhere else, because between trips they live in a closet, not an airport.
The Long-Haul Traveler
Two weeks or more, often several cities, often several climates. A large checked bag within 62 linear inches, plus a carry-on for the things you would rather not lose. Weigh it at home. A large suitcase reaches 50 pounds well before it is full.
The Buy-Once Traveler
You research, you buy properly, and you keep it for a decade. The mistake here is buying for the biggest trip you might take rather than the trip you take most. Buy for the second one, and add a size later if the first ever arrives.
How to Measure Your Luggage
Whichever of those you are, three things decide whether a bag passes.
Every dimension includes wheels, handles, and exterior pockets. A suitcase sold as 22 inches is often 23 with its wheels. This is the single most common reason a bag gets stopped at the gate.
Linear inches means addition, not multiplication. A bag measuring 28 x 19 x 12 is 59 linear inches, comfortably inside the 62-inch limit. Volume never enters into it.
The margin is closing. More airlines now use sizers and automated scanners at the gate rather than trusting the honor system.
The 24-Inch Question
A suitcase sold as "24 inch" is not measured the way an airline measures. That number is the height of the bag, usually including the wheels, and it says nothing about the other two dimensions.
So, plainly: a 24-inch suitcase is a checked bag. It is not a carry-on anywhere in the US. A 28-inch bag usually lands just under 62 linear inches, but "usually" is doing real work there, and some cross the line. Measure your own, all three sides, and add them up.
Where Airlines Differ
American, Delta, United, JetBlue, and Alaska all set carry-on at 22 x 14 x 9 inches. Southwest allows 24 x 16 x 10. Spirit and Frontier include a free personal item of roughly 18 x 14 x 8 and charge for anything larger.
Checked bags are more uniform: 62 linear inches and 50 pounds across the majors. Frontier and Spirit hold the size limit but drop to 40 pounds. Overweight fees usually start around $100.
Abroad, cabin limits are tighter and less consistent. Ryanair gives you 40 x 30 x 20 cm free and charges for 55 x 40 x 20 cm overhead. easyJet allows 45 x 36 x 20 cm free. British Airways is at the generous end with 56 x 45 x 25 cm. From July 2027, EU rules guarantee every passenger a free personal item of 40 x 30 x 15 cm.
For exact dimensions, packing volumes, and weights across the Aviator Collection, see the Size Guide.
