How to Measure Luggage For Air Travel

Last Updated on April 15, 2020

We all want to take our favorite things with us when we travel.

But if everyone was able to take unlimited bags they wouldn’t all fit inside the plane. Space inside planes is limited.

And if your plane was too heavy it couldn’t actually take off!

Heavy planes are less fuel efficient, more expensive and more damaging to the environment.

That’s why airlines have size restrictions on both carry on and checked baggage. And because they are sometimes greedy and want to charge you extra fees when they can.

This post shows you exactly how to measure luggage dimensions for air travel.

It’s your responsibility to check the size of your bag before you fly against your airlines size restrictions to make sure you don’t encounter problems.

How is Luggage Measured?

The way that you measure luggage and the way that airlines measure luggage will be slightly different.

At home, you’ll use a simple tape measure.

At the airport airlines usually use a carry-on sizer. This is the metal frame that you need to place your carry on bag inside.

A typical carry on luggage size measuring sizer

If your bag doesn’t fit inside the frame then it’s too big!

Most times you won’t actually need to put your bag in this sizer unless requested. That means a protruding wheel or handle might not cause a problem. But if the airline staff asks to test your bag and it doesn’t fit you will be forced to check your bag and may be charged additional fees.

If you don’t like to take risks then it’s best to measure your suitcase using a tape measure at home.

It’s also a good idea to research the real size of your suitcase before you buy it. Don’t be afraid to take your own tape measure into the store with you.

How to Measure Luggage Size At Home

If your carry-on suitcase is standing on its wheels in front of you:

  • Height is up and down.
  • Width is left to right.
  • Depth is front to back.
Dimensions for luggage are usually written in the following order – Height, Width, Depth i.e. 22 x 14 x 9 inches.

Simply take a tape measure and check the size of your bag. It’s not that hard to do but I know what you are going to ask…

Do the Wheels Count When Measuring Luggage For Carry On?

This depends on who is doing the measuring!

Luggage manufacturers know you want to buy a large, spacious suitcase. So they often conveniently ignore protruding handles and wheels. They will often advertise a suitcase as “carry-on size” when technically the wheels or handles mean that it’s over-sized for some airlines.

They can do this because there is no official carry on luggage size. Every airline sets their own limits. So the manufacturers have plausible deniability. But they they know fine well what they are doing.

In contrast, airlines do include wheels when measuring luggage! Carry-on luggage is measured including the wheels, handles or any other protruding part of the suitcase.

Hmm… This means you can’t really trust the manufacturer’s advertised luggage measurements.

That’s why you need to use your own tape measure and not rely on the size listed by the suitcase manufacturer or even the store selling the bag.

Pro-Tip About Rolling Luggage Dimensions

The 4 wheels on spinner carry-on luggage that you can roll while standing up and spin 360 usually have wheels that stick out a lot.

In comparison, you’ll find on cabin bags with 2 wheels are usually recessed into the bag. This means that you usually have more “legal” space when using 2 wheeled cabin bags than 4 wheeled spinner bags.

A 4-wheeled spinner suitcase with protruding wheels compared with a 2-wheeled suitcase with recessed wheels

Wheels do count when measuring luggage. This means that 2-wheeler suitcases with recessed wheels usually have more space inside the bag that 4-wheelers with protruding wheels.

Do Wheels Count In Checked Baggage Measurement Too?

Yip. The same applies for a checked bag.

Checked bags do include wheels in the luggage measurements.

So to measure checked bags you need to use your tape measure and include the wheels while you do it.

To measure the height place the suitcase against a wall and use a pencil to draw a little mark at the top against the wall. You can then measure from this mark to the floor to get the height of your checked suitcase including the wheels.

How Do Airlines Measure Checked Baggage?

Airlines don’t use sizers for checked baggage, so how do airlines measure checked baggage?

When you are checking your bag at the check-in desk the weight of the bag is automatically taken.

If a bag looks like it might be too large the check-in steward will measure your suitcase with a measuring tape.

If your bag is found to be oversized or overweight be prepared to get handed a hefty bill to check your bag.

And not only that… they’ll hit you again with an excessive fee on the return journey!

A bag that is oversized could easily cost you $300 extra per trip. And more if it’s also overweight!

With Dimensions Of Luggage… What Are Linear Inches Anyway?

Some airlines will list their luggage carry on size limits or checked luggage size limits in something called linear inches.

Linear means “in a straight line”.

This means they don’t mind so much the exact shape of your suitcase. But if you take the 3 dimensions, height, width, and depth and do the math to add them together they must be less than advertised linear inch limit.

Take this example…

What Size Of Bag Is 62 Linear Inches?

Linear inches simply means adding the height, width, and depth together. Here is an example of a 62 inch bag.

This AmazonBasics suitcase is 30.9 x 17.5 x 12.9 inches including the wheels. If you add those three numbers together you get 61.3 inches.

So this bag is just under the 62 linear inch check-in bag limit for US airlines.

To get a feel for the size, a 62 linear inch suitcase is roughly about 68% larger than a standard carry on bag. It’s not twice the size, it’s like 1 carry-on suitcase plus 2 thirds of a second carry on.

Or to put it another way… if you packed 6 t-shirts in a carry on you could pack 10 t-shirts in a 62 linear inch suitcase and they would take up the same proportion of your bag.

Don’t Forget To Measure The Weight Of Your Luggage

In addition to size restrictions, luggage often has weight restrictions too.

You should measure the weight of your bag and check it against your airline’s rules to make sure your bag is not over the limit.

This is especially important if you are flying internationally.

You can measure the weight of your luggage using a handheld luggage scale.

You simply strap the scale onto your handle, pick up your suitcase using the scale and let it dangle for a moment. The luggage scale will display the weight of your suitcase.

It’s much better to know the weight of your suitcase before you arrive at the airport. Especially if you are flying with an airline with very restrictive weight limits or you have guilty of over-packing.

Again if your check-in bag is overweight then airlines will punish you with high fees. And again they will hit you on the return journey too.

A bag that is overweight could cost you an extra $300. If it’s overweight and oversized then you could easily be looking at adding an extra $600 to the price of your flight.

You really need to be careful with these bloodsuckers!

If you need to slim down your suitcase then I recommend reading my guide to packing light and traveling light to help you shed some weight from your bag.

The Verdict

It’s better to make sure you know how to measure luggage correctly at home so that you don’t run into any arguments or even excessive fees at the airport.

Like this passenger did while flying with United Airlines:

Give them half a chance and the airlines will screw you for extra fees. It’s better to know how to measure your suitcase before you fly to make sure you are not a victim of this practice.

And don’t let the luggage makers trick you into buying a bag labeled “carry on” when it’s too big to be a legal carry on.

What do you think? Do you have any tips about how to measure a bag for air travel? Let us know in the comments below if you have anything to add or any questions.