Measuring a travel bag? How to get size and capacity right
- , by Miquell Hellings
- 11 min read
It is best to measure a travel bag before you start packing or booking. That helps you avoid finding out your bag is just slightly too large for hand luggage, has to go in the hold unexpectedly, or causes extra charges at the airport. By measuring the length, width, and height the right way, you can quickly see whether your bag fits within the allowed dimensions. This is especially important with soft travel bags and travel bags with wheels, because protruding parts such as wheels and handles are usually included.
On this page, you will read how to measure a travel bag correctly, which dimensions you should use for different types of luggage, and what to look for if you want to compare your bag with airline requirements. If you are also looking for the best travel bags with wheels, this will help you choose a model that is practical and still within the right size range.
How do you measure the dimensions of a bag?
You should always measure a travel bag from the outside. Use a tape measure and place the bag on a flat surface. Then measure the three most important dimensions:
- Length - from left to right at the widest point
- Height - from bottom to top, including fixed parts
- Width or depth - from front to back at the deepest point
Does your bag have wheels, a telescopic handle, reinforced corners, or a front pocket that sticks out? Then include those parts if they affect the outer dimensions. Airlines look at the total external size, not just the textile main compartment.
With a soft travel bag, it is smart to measure it when lightly packed. Empty, a model can look flatter than it does in use. So measure it as you would realistically take it on a trip.
Want a full step-by-step guide and examples? Read the Travel bag dimensions: complete guide.
What size travel bag do you need?
The right size depends on how you travel. For a short trip, a compact travel bag is often enough, while for a week or longer you need more capacity. So do not just look at the outer dimensions, but also at the purpose of your trip.
Compact travel bag for short trips
For a weekend away or a short city break, a small travel bag is usually enough. This size is useful if you want to travel light and can sometimes also be used as hand luggage. A soft bag is especially practical here, because it fits more easily into an overhead bin or car boot.
Medium travel bag for a week away
If you are travelling for about a week, a medium-sized travel bag is often the best choice. You get enough space for clothes, shoes, and toiletries without the bag becoming awkwardly large. This size is common among travel bags with wheels, because it combines comfort and capacity well.
Large travel bag for longer trips
For longer holidays or trips where you are taking a lot of things with you, you will usually end up choosing a large travel bag. Then it is extra important to pay attention to the maximum dimensions and weight if you are flying. A large bag may seem practical, but it can be less convenient if you often have to lift it, take stairs, or transfer between connections.
Measuring a travel bag for hand luggage
If you want to use a travel bag as hand luggage, you need to measure carefully. Every airline has its own size and weight rules. A difference of just a few centimetres can already mean you have to pay extra or that the bag still has to go in the hold. You can find more details in the Hand luggage dimensions: complete guide.
So always measure including:
- wheels
- handles
- protruding pockets
- hard protective edges
Then compare the result with the conditions of your ticket and airline. Also pay attention to the difference between a small personal item and a larger cabin suitcase or cabin bag.
What is hand luggage 40 x 30 x 20?
40 x 30 x 20 cm is a commonly used size for a small personal item that fits under the seat in front of you. This size is often used for a small backpack, laptop bag, or compact travel bag. It is not a standard size for all airlines, but it is a well-known limit on budget flights.
Also view the overview of airline rules for 40 x 30 x 20 to see how airlines handle this.
Want to choose a suitable bag right away? View the 40 x 30 x 20 hand luggage bags.
If you fly with Ryanair, 40 x 30 x 20 cm specifically applies to the free small personal bag. So that is not the same as the larger 10 kg cabin bag. For Ryanair, the 10 kg cabin bag size is 55 x 40 x 20 cm. Keeping those two separate helps you avoid mistakes when choosing or measuring your bag.
Looking for a bag in that size? View the 55 x 40 x 20 hand luggage suitcases and bags.
Why soft travel bags are popular as hand luggage
A soft travel bag often works better with changing hand luggage rules than a hard suitcase. The material gives a little and the bag is easier to store in the overhead compartment or under the seat. Especially if you are looking for the best travel bags with wheels, it is smart to look at models that appear compact but are still efficiently organised.
Do note this: a soft bag may be a little more flexible, but officially it still has to stay within the maximum dimensions. Packing it too full can quickly make the bag thicker than allowed.
Measuring a travel bag for checked luggage
Measuring is also important for checked luggage. Not only the weight matters, but sometimes the total size does too. Many airlines look at the outer dimensions or at a combination of length, width, and height. As a result, a large travel bag with wheels can exceed the allowed limit faster than you expect.
With Ryanair, you need to keep baggage categories clearly separate. The 20 kg check-in bag has a maximum size of 80 x 120 x 120 cm. The 23 kg check-in bag also has a maximum size of 80 x 120 x 120 cm. So these are checked luggage dimensions, not hand luggage dimensions.
Always check before departure:
- the maximum dimensions of your checked luggage
- the allowed weight
- whether your ticket includes luggage
- whether a soft travel bag still stays within the limit when fully packed
Calculating the litres of a travel bag
Besides centimetres, many people also look at capacity in litres. That helps when comparing models. Especially when two bags have roughly the same outer dimensions, the number of litres says something about how much you can actually fit inside.
A simple way to estimate capacity is:
length x width x height in centimetres, divided by 1000 = capacity in litres
This works best if the bag has a fairly rectangular shape. With rounded or tapered travel bags, it is mainly an estimate. Manufacturers often state a more official litre capacity, but calculating it yourself helps you compare models more accurately. If you are unsure about capacity, also look at how many litres of travel bag you need.
What does a 62-inch bag mean?
A 62-inch bag usually refers to the total sum of the length, width, and height in inches. Instead of using three separate measurements, one combined figure is used. You mainly see this in international baggage rules for checked luggage.
Converted, 62 inches is about 157 cm in total. So that does not mean one side of the bag is 157 cm, but that all three dimensions together add up to around that total. This system is especially relevant if an airline does not work with separate maximum side lengths, but with a total combined size.
Common mistakes when measuring a travel bag
Measuring a travel bag seems simple, but in practice things often go wrong in the details. As a result, a bag may seem suitable at home, but still be rejected at the airport.
- Only measuring the main compartment - wheels, handles, and protrusions usually count too
- Measuring a soft bag when empty - once filled, it often turns out larger
- Using the wrong baggage category - a personal item is different from cabin luggage or checked luggage
- Not checking the weight - even if the size is correct, the bag can still be too heavy
- Assuming airline rules based on a previous flight - conditions vary by airline and ticket type
What should you look for in the best travel bags with wheels?
If you choose a travel bag with wheels, size plays an even bigger role. The wheels and pull handle take up extra space and make it easier for a bag to exceed a limit. At the same time, wheels offer a lot of comfort over longer distances in stations, airports, and cities.
When comparing models, look at:
- the total outer dimensions including wheels
- the empty weight of the bag
- the layout of the main compartment
- whether the bag stays upright stably
- how smoothly the wheels roll
- whether the bag is also comfortable to carry by hand
For anyone who wants to combine convenience with flexibility, travel bags with wheels are often a smart alternative to a hard suitcase. This can be especially practical for car trips, train journeys, and short flights.
Practical checklist before you travel
- Measure the bag on the outside on a flat surface
- Include wheels, handles, and protruding parts
- Measure a soft travel bag when lightly packed
- Check both dimensions and weight
- Compare the measurements with your airline and ticket type
- Check whether your bag falls under hand luggage or checked luggage
- With Ryanair, use the right category: 40 x 30 x 20 cm for a free small personal bag and 55 x 40 x 20 cm for a 10 kg cabin bag
Frequently asked questions about measuring a travel bag
Do you measure a travel bag empty or packed?
A soft travel bag is best measured when lightly packed, so you get a realistic idea of the final outer dimensions. A hard bag can usually be measured empty, because the shape stays the same.
Should wheels and handles be included in the measurement?
Yes, usually they should. Airlines count the total outer dimensions. Wheels, fixed handles, and other protruding parts can therefore be decisive.
How do you know whether a travel bag can be taken as hand luggage?
By comparing the outer dimensions of your bag with the hand luggage rules of your airline and ticket type. Do not just look at general guidelines, but always check the current conditions for your specific flight.
What is more important: litres or dimensions?
For flying, dimensions are more important because airlines check those. Litres mainly help you compare different models and estimate how much you can take with you. You can read more about this in our guide to travel bag dimensions.
Is a travel bag with wheels more practical than a regular travel bag?
That depends on your trip. A model with wheels is comfortable on flat surfaces, while a regular travel bag is often lighter and more flexible. If you walk a lot, lift often, or travel on uneven ground, a bag without wheels may actually be more practical.
Where can you compare different travel bag sizes?
By putting product dimensions, capacity in litres, and use case side by side. At ByMetz, you will find different kinds of hand luggage travel bags, making it easier to decide which size suits your trip and baggage requirements. If you are still unsure about the right size, also check which travel bag size suits your trip length.