Here at South East Asia Backpacker, we get asked a ton of questions about choosing the right backpack for travel.
And the one that we’re asked over and over again is… “How big should my backpack be?”
While the in-depth answer differs for everybody, the simple answer is almost always “smaller than you think.”
Keep reading as we dive into the different sizes of backpacks and uncover which is most suitable for you!
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The Best Backpack Size for Travelling – Everything You Need to Know! 🤘
Good To Know!
When we mention backpacking in this article, we’re talking about it in the travel sense – like a backpacking trip around Southeast Asia – rather than backcountry hiking and trekking.
Backpack Volume ⚖️
Backpack volume is measured in litres and is touted as the most important factor to consider when purchasing a travel bag.
But it doesn’t tell the whole story.
The size, shape and materials of a given travel backpack will affect how much gear you can fit into and how easily you can pack the bag.
For example, a 40-litre, triangular backpack will be tougher to organise than a rectangular shaped bag of the same volume. Likewise, a backpacking pack made of a tough, rigid material won’t flex as you fill it to the brim. This can make packing and carrying a full load more challenging.
A rectangular backpack made of flexible, yet robust materials like nylon will generally be the easiest to pack and carry. Backpack manufacturers know this and most produce a quality range of travel backpacks that fit the bill.
But that still doesn’t answer the question — What size bag do I need for travel? We surveyed our audience of travellers to see what size and brand of bags are most common among backpackers.
The answers fit into four size brackets: 25-30 litres, 40-46 litres, 50-60 litres and more than 65 litres.
Looking for a Duffel Bag? 👀
Check out our list of the best duffel bags for travel for everything you need to know about travel duffels!
25-30-litres
Best for…
A 25-30-litre travel pack is best for a city break or long weekend trip. Some very light packers can get away with travelling indefinitely with a bag of this size but they are in the minority. Most long-term travellers require a larger bag than this.
Some backpackers will use a 25-30-litre bag as a daypack because it’s big enough to carry everything you’ll need for a day out. Be aware though, unless you pick up a collapsible 25-30-litre bag, it can be difficult to carry along with your main bag.
Not ideal if…
A bag of this size isn’t suitable for heavy packers or those who like their creature comforts. If you need more than a few outfits, then you’ll have to size up. These bags also aren’t ideal for travelling in cold environments. Warm clothes are bulky and will quickly fill the limited space!
- Price Range: $$$
- Best Feature: Loads of usable space and suitcase-style opening
- Feature To Improve: Limited external pockets and nowhere to store a water bottle
40-46-litres
Best for…
A bag in this size bracket is a traveller’s best friend! They have much more usable space than sub-30-litre bags but are generally lightweight and comfortable to carry.
They’re suitable for short breaks or longer trips. Most backpackers can travel for months, if not years, with a backpack in the 40-46-litre range! It’s easy to fit in a week’s worth of clothes, as well as all your travel essentials. If you’re clever with the way you pack, you should also have a bit of spare room for travel gadgets or bringing souvenirs home!
This size bag can also usually be carried as hand luggage. This means you shouldn’t need to check a bag, leaving you able to skip the extra queues and avoid waiting at the luggage carousel.
✈️ Always check with your airline to see their full carry-on limits.
A Note On Expandable Backpacks 📝
While not super common, finding the right expandable backpack for you can be a game changer. My mind was blown the first time I used an expandable Tortuga backpack. I no longer needed a 25-litre and 35-litre back. With a quick zip, I had one bag in my collection that fit both roles perfectly! It even had a laptop compartment! You can find other expandable backpacks that go up from 35 to 45 litres or more.
Not ideal if…
For those travelling around the world and visiting extreme climates, bags in the 40-litre range might be too small. Warm clothes are bulky and take up a lot of valuable space!
These bags also aren’t great for particularly heavy packers. While some backpackers pride themselves on carrying as little as possible while they travel, others like to bring all their home comforts. If this sounds familiar, you might want to consider a larger bag or try travelling with less.
👉 Read More: The Best 40-litre Backpacks
- Price Range: $$$
- Best Feature: Carry on compliant and clamshell opening
- Feature To Improve: No real water bottle pockets
50-60-litres
Best for…
Backpackers on long trips across many different climatic zones. The space offered inside these bags means you can afford to carry extra jumpers, coats and a few pairs of shoes along with all your other travel gear. They’re also good for people who want to travel with a ton of luxuries!
The nice thing about these bags is that although they’re significantly larger than the 40-46-litre backpacks, they don’t stand out too much or feel unwieldy to carry.
If your backpack feels cumbersome or unmanageable, check it fits correctly. Poor-fitting backpacks can be very uncomfortable to carry! See if you can try a backpack of this size on before buying it. Check for padded straps and make sure the hip belt fits nicely – you’ll rely on this to support the bulk of the pack’s weight as you walk. Sternum straps are also important with larger backpacks!
Not ideal if…
You want to travel hand luggage only. These bags will almost certainly need to be checked on planes. This means you’ll also need a smaller daypack for your hand luggage.
They’re also not great if you want to be super light on your feet while travelling. Sure, they don’t feel too cumbersome but you’ll notice how much gear you’re carrying – especially if you’re trying to take local transport like buses, tuk tuks or moto-taxis!
- Price Range: $$$$$$
- Best Feature: Main pack and daypack all in one setup
- Feature To Improve: It's heavy and expensive
65+ litres
Best for…
Honestly, a large travel backpack over 65 litres shouldn’t belong in the realm of backpackers. They’re more built for long backcountry trips. As such, many of them contain the features you’d expect to find in a hiking backpack, which are useful on the trail but can get in the way while travelling. However, the sheer amount of storage space and various storage compartments in these large backpacks means you’ll be able to fit in all your travel accessories with ease!
Travellers who really can’t fit all their gear into a smaller backpack will enjoy the space of a 65-litre pack but its limitations will likely prove too much for most backpackers.
Not ideal if…
A backpack of more than 65 litres will be substantially heavier than its smaller brethren. This is even true before it’s been filled. It will be made from tougher, more durable materials which allow you to carry more. But these come with a weight penalty of their own.
When filled, you can expect a backpack of this size to weigh more than 20kg. This is an uncomfortable amount for the average person to carry!
They can also be very unwieldy, especially if you’re trying to navigate through busy streets or use public transport.
- Price Range: $$$
- Best Feature: Detachable daypack
- Feature To Improve: It's very bulky when full
Conclusion
At the end of the day, choosing what size backpack to buy comes down to personal choice. See how much gear you have and decide from there what size bag you’ll need.
Honestly, most of us can easily travel with a 40-litre backpack like the Osprey Farpoint or Fairview. You probably don’t need to travel with more than you can fit into one of those backpacks.
The best advice we can give when it comes to choosing a bag is: take less stuff. It allows you to travel light, avoid checked baggage fees and easily walk miles with all your gear on your back.
Tim Ashdown | Gear Specialist
After a life-changing motorcycle accident, Tim decided life was too short to stay cooped up in his home county of Norfolk, UK. Since then, he has travelled Southeast Asia, walked the Camino de Santiago and backpacked South America. His first book, From Paralysis to Santiago, chronicles his struggle to recover from the motorcycle accident and will be released later this year.
