How to Measure Carry-On Bags & more luggage questions (2023)

Getting ready to air travel is exciting; we pick our seats, plan our traveling outfits, and download some entertainment for the flight. And then we begin to pack. That’s when we decide what bags to carry onboard the plane. And we start rationalizing… ‘duffel bags will fit the bag sizer if they’re squished a bit.’ And… ‘the airline staff never check. I’ve seen people board the plane with huge backpacks!’ And… ‘what size is a medium suitcase anyway???’ Though sometimes we’re right and our oversized bags will make it on the flight, other times our lack of foresight with the guidelines can backfire. Learning how to measure carry-on luggage will make all our trips easier.

On a multi-stop overseas trip, I was careful to pack in a duffel perfectly sized for the longest leg of the journey, but when our flight was changed, and we were directed to a regional flight my bag was pulled. Suddenly I was left with only a small daypack and lots of worries about what had been in that duffel that I should have hand carried. Fortunately, I reunited with my duffel in South Africa, but I suffered through 16 hours of travel anxiety on the way. Since that episode I’ve been careful to check with each airline for its carry-on allowance, measure my luggage, and have everything organized before heading to the airport.

train station with passengers all with different sized luggage.
Image by songping wang from Pixabay

Everything you need to know about cabin bags

Since our recent article on packing light for 2 weeks, we’ve had questions finding the right size bag. We’ve tried to address these here, but be sure to send along any more questions you might have.

Lesson One: Check with every airline you’ll be flying before choosing a bag.

Though most airline’s allow passengers one carry-on to go in the overhead bin and one personal item to fit under the seat, be sure to check ahead of time. Even if you know the linear inches your preferred carrier allows for domestic flights, there are often different size limits for overseas flights. And there are different carry-on specifications for every fare type.

EXAMPLES – carry-on luggage dimensions:

  • Average dimensions for domestic flights – 22″ x 14″ x 9″
  • Average dimensions for international flights – 21″ x 13″ x 9″
Note that these are averages. Depending on your airline and fare class your carry-on allowance may differ. Budget airlines may charge additional fees for any carry-on item.

Lesson Two: Note if there are weight restrictions for your bags.

The airline may indicate luggage weight restrictions on their website. Many of us weigh our bags before checking luggage but forget that some airlines will also impose a weight limit on carry-on baggage. Don’t be stuck having to discard clothing and essential gear at the gate.

Lesson Three: Always be prepared for a mandatory gate check.

Pack your most important items – passport, valuables, medications,etc. – in your small personal item. We carry small backpacks that’ll fit under the seat in front of us, but in your case, this might be a laptop bag, diaper bag, or your camera bags. If the airline staff gate check your larger cabin bag, having your necessities in your carry-on will let you travel much more easily. You can rest assured that everything you need for the next few hours is safely with you.

NOTE: Always have electronic devices with lithium batteries ready to transfer to your personal item if necessary. Lithium batteries are a fire hazard and cannot be packed in a checked bag. It’s a good idea to have a packing cube with one day’s clothing also ready to transfer.

airport at dawn. man carrying medium sized suitcase.
Image by Sam Williams from Pixabay

What size is a medium suitcase?

Of course, this depends on you! Most travelers consider a medium suitcase to be the size they can handle easily with enough space for seven days’ worth of clothing. The size of this suitcase will vary if the traveler is driving vs. flying to the destination. If you’re tossing your bag in the trunk of the car, there are many luggage sizes that’ll work. But a large suitcase will require checking on a flight. So, for our purposes, let’s consider a medium suitcase to be the maximum carry-on sized luggage for a flight, the size that will fit in the overhead compartment.


How do you measure carry-on luggage?

Every airline has a different standard for hand luggage. Some will specify maximum dimensions (e.g. maximum length, width, and depth of luggage) and others specify the maximum linear inches (linear means length + width + depth) In the latter situation a bag that is 25″ x 10″ x 10″ is allowed as hand baggage as is a bag that is 21″ x 16″ x 8″.

Measuring your bag at home

how to measure carry-on luggage. include wheels and handles

Once you’ve determined the maximum size for your aircraft, it’s time to measure those bags. You can do this easily with a tape measure. But for greater accuracy you could mark straight line dimensions on the wall or trace your bag on paper. Measure each dimension at its widest point.

Remember the luggage dimensions of your bag INCLUDE the handle and wheels! The bag on left (EC International Carry-On ) measures 21″ x 14″ x 8″, including 2 inches to the bottom of the wheel.

If you’re looking for a new bag, most luggage manufacturers will indicate whether their bag fits the size restrictions for domestic travel carry-on. After my scare with my duffel, I purchased this bag with spinner wheels for international travel. It has expandable capacity so that on domestic flights I have extra space, but on overseas flights I don’t worry that it will be gate checked.

Checking weight of cabin luggage

You can get the estimated weight of your carry-on bag, by weighing yourself and the bag on your bathroom scale. But if you need a more specific weight of the bag, consider purchasing a portable luggage weight scale.

If you’re traveling on smaller planes with maximum weight limits note that four-wheel spinners are noticeably heavier than other bags. Your best option might be a standard size backpack or duffel. Or better yet, a duffel that has backpack straps! Both of the bags below are of similar capacity (30 liters) but the four-wheel spinner weighs 6.1 lbs. vs the soft-sided duffel at 2.1 lbs.

Side by side comparison of two medium sized carry-on bags.

Similarly, a hard shell bag will be heavier than a soft-sided luggage. But a hard suitcase may hold up better longer, especially if you ever need to check the bag. Baggage handlers can be rough on checked-in luggage.

Where can I donate old suitcases?

If you’re purchasing a new bag for your next trip, consider donating your old suitcase to a shelter or foster care program. The kids in these programs often carry their worldly goods in plastic bags. Look into your local foster programs or donate your old suitcase through one of the organizations.:

Note: Because of the materials used in manufacturing luggage, most suitcases can not be recycled.


This post is part of our Travel 101 series of posts that will prepare you for your trip. If you’re just beginning to plan, I’d suggest you start with the first in the series – Pack Light, Travel Easy.

This article contains affiliate links. I may earn a small commission, at no expense to you, if you purchase an item on this website. Read our DISCLOSURE.

How to measure carry-on luggage, what size is a medium suitcase, and suggestions for donating used luggage.
How to measure carry-on luggage, what size fits your airline’s cabin allowance, and suggestions for donating old suitcases.

TravelingTulls is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. We are not provided with any products by Amazon but receive a small fee if you purchase an item through our link.

Leave a Reply