There is a standard size for carry-on bags that’s used by all of the major airlines.
There is not a standard size for carry-on bags. Jet Blue is one of the most generous carriers, permitting you to bring aboard a carry-on bag that measures 24 x 16 x 10 inches. In 2014, United, American, and Delta all changed the size limits permitted for carry-on bags to 22 inches long by 14 inches wide by 9 inches deep. George Hobica of said, “The three majors now have that 22 by 9 by 14 inch rule and have been known to enforce it to the inch in some airports at busy travel times, occasionally at the gate, but sometimes even before entering the TSA security lines.”
While large domestic carriers seem to turn a blind eye to the weight of a carry-on bag, international carriers and smaller aircraft that are flown virtually anywhere in the world often have strict weight restrictions for every piece of luggage that a passengers brings on the plane. The smart thing to do is to visit your carrier’s website before you fly to see what the current rules are.

Carry-on bags are really all the same, it’s not worth it to buy a better one.
A well-designed carry-on can get past airline scrutiny and allow you to pack what you need. Steve Jordan, senior product developer of luggage at L. L. Bean, says that the company sees “robust sales of our carry-on luggage as the airlines continue to charge fees for checked bags.”
In your quest for the perfect carry-on bag, make sure that the dimensions listed include any wheels that protrude from the bag. Probably the hottest trend right now is luggage that expands for packing and then compresses for traveling, allowing travelers to squeeze more into a bag. At the top end are bags like the Briggs & Riley U122cx Baseline, which measures 21 by 14 by 7.7 inches when closed but expands 25% for packing.

The TSA has relaxed the laws about what they allow in a carry-on bag.
No, they haven’t, but this was apparently news to domestic passengers who packed more than 2,200 firearms in their carry-on bags in 2014, which the TSA said was a 22% increase from the year before. There is a long list ( of other items that are forbidden in carry-on bags, from pepper spray and knives to baseball bats, ski poles, lacrosse sticks and realistic replica firearms.
On the other hand, there’s a new item that the TSA recently said must go into your carry-on and not in your checked bag: e-cigarettes. The FAA made the call to ban them from checked luggage because they utilize lithium batteries and there’s a concern over overheating or fires inside the cargo hold. You still can’t smoke them on board, however.

It’s the flight attendant’s job to make sure your carry-on fits.
“Making sure a bag fits doesn’t mean it’s my job to make it fit,” says Heather Poole, a flight attendant and author of Cruising Attitude: Tales of Crashpads, Crew Drama, and Crazy Passengers at 30,000 Feet. “Or lift it! Heck no. I can help you, but I’m not doing it for you. We’re doing it together.”
Stowing bags properly is not just a matter of efficiency but safety and departure time. The gate agent says Poole, “isn’t allowed to shut the aircraft door

until all binds are closed and passengers are seated. If the bag doesn’t fit, off it goes.”
It also comes down to money, since delays are costly. That’s also true for flight attendants, who, remarkably, are not compensated for their time helping you stow your bag. “We’re paid for flying time only,” says Poole. “The time clock doesn’t start ticking until the brakes are released and we back away from the gate.”

The airlines may nickel and dimes us, but at least they’re not charging for carry-on bags.
Frontier charges between $25 and $35 for carry-on bags, depending on what level of economy-class ticket you have. Think you can outsmart them and just gate check? Think again. They charge $60 for any bag that has to be gate checked. Spirit is even more onerous, charging anywhere from $26, if you pay during online check-in, to $100 if you wait to pay at the gate. Allegiant is another airline charging for carry-on bags. These carriers do permit one free “personal item,” such as a purse or backpack, but it can measure no more than 18 by 14 by 8.
So will the major US carriers follow suit and begin charging us for carry-ons? George Hobica of says that it’s “very doubtful this will happen, but never say never.”

Carry on Luggage
Carry On Regulation

Leaving on the next flight! Will my luggage arrive when I do??