When choosing the best hiking backpacks for under 100 liters, you should not take a big one to be sure that everything will fit in it. Also, a big (empty) bag weighs more than a small one – an unnecessary weight you’ll have to carry.
So, how do you choose the right size backpack? This is one of the questions you have to ask yourself to choose a good backpack for hiking. And it’s the one I’m asked the most often.
Before seeing how to choose the best volume for your hiking backpack, let’s quickly see how to find your way once you are in front of all these backpacks in stores or on a website.
Volume, capacity, liters
We often talk about volume, but you will also hear about capacity, liter or even capacity. These terms mean the same thing and are measured in liters (noted L).
Generally, the volume is indicated in the model name. For example, Supersacderando 35 would be a backpack with a volume of around 35 L.
This number represents the volume of the main compartment plus the volume of all pockets. Depending on the number of pockets and their location, two bags of the same volume may not appear to you as such.
Sometimes you will see two numbers. For example: Supersacderando 55 + 10. The second number “10” indicates the volume of the extension that is present on some backpacks. This extension is generally present under a raising flap (adjustable in height), as in the image on the right.
To properly choose the volume of your hiking backpack, I’m not going to give you standard volumes (in any case, not right away) because it doesn’t really make sense. It is not enough to ask myself: “François, I want to hike for 3-4 days, which capacity should I choose?” “. In one case, I would advise you perhaps 30 liters. In another, maybe 50 liters.
Instead, I will walk you through a few questions so that you can determine your needs and constraints and make the right choice.
Ask yourself the right questions!
When you choose a backpack, the obvious goal is that all your stuff can fit in without having to pack with your feet to close it (which is a bad omen for the seams and zippers).
The first question to ask yourself is: what types of hikes are you going to do with your backpack?
The ideal would be to have a backpack for each type of hike so that it is very well suited. But in practice, this is not really possible – especially financially!
Depending on your budget and the type of hike you are going to do, I advise you to have a single fairly versatile backpack, or two (or even three) backpacks if you practice very different types of hikes. For example, you can have a 30-liter backpack for short hikes and a 50-liter bag for long hikes.
Obviously, if you want to use a bag for several types of hikes, it must contain the stuff for all these types of hikes. So it will happen that your bag is not full when you go on a hike that does not require a lot of equipment. In this case, the compression straps are practical, to prevent your equipment from “moving” too much inside. The vacuum bag is a little heavy (compared to a smaller adjusted bag) but it saves you from buying several bags.
Now let’s look at a few different types of hikes and some factors that affect the contents of your bag:
- The number of hiking days.
- Where you spend the night (refuge, tent, tarp, etc.) – for hikes lasting several days.
- If you need specific equipment (crampons for playing on the ice, kibble for your dog, etc.).
- If you are completely independent (water and food), if you get food, if you take certain meals in shelters.
The second question to ask yourself: under what weather conditions do you plan to hike?
The colder it is, the more clothes you will need to bring (and a “warm” sleeping bag) and the larger your bag will need to be. If the conditions are wet, you will also need waterproof and spare clothing.
Are you going to carry other people’s equipment?
This can be the case if you hike with children or people of a smaller size. This will influence the choice of the volume of your backpack. Likewise, if someone is carrying some of your equipment.
Are you going to put all your stuff inside your bag or do you plan to hang it outside?
Hanging things on your backpack allows you to gain versatility. But beware, the hanging material must be stable, it should not be annoying and it can be protected from the rain if necessary.
Do you need to bring “unusual” equipment in your backpack?
The 4 previous questions allow you to determine the “classic” needs and constraints for choosing the volume of your backpack, but there are certain personal needs or constraints that only you can know.
3 tips for determining the volume of hiking backpack you need
As we have seen, the ideal is a backpack:
- Not too small, in which all your equipment might not fit.
- Not too big, which would not be practical, in which your material would “move” and which would not be optimized from a weighted point of view. In addition, with a bag that is too large, you would be tempted to fill it with unnecessary things.
If you need to remember only one thing from this article, it is surely this advice: choose your backpack once you have all the rest of your equipment.
It’s the only way you know the exact volume you need. You will probably use your backpack for different types of hikes (which you have already determined previously). So collect all the equipment you will use on the hikes where you will take the most equipment, without forgetting the water and food.
Then, I suggest you use one of the following 3 tips to determine the volume you need:
- Tip 1: Borrow backpacks of different capacities from friends and try to bring in all your equipment, including food and water.
- Tip 2: Fill trash bags of different capacities with all your equipment (without forgetting food and water) or a bag of which you know the capacity (travel bag for example).
- Tip 3: Go to the store with all your equipment (food and water included) to try different backpacks. In addition, as the backpacks have different shapes, you will be able to make sure that all your equipment fits in the model that interests you. The disadvantage is, of course, arriving with all your equipment in a store …
If you ever hesitate between two volumes (to within 5 or 10 liters), I would advise you to take the larger one, so that it is easier to access your equipment. When everything is really “packed”, it is not very funny.
Average approximation depending on the type of hike
As we have seen, you need to determine the volume of your bag according to your needs and constraints. I am a little reluctant to give you standard values because it is too general. For example, for the same hike, a person can have a 35 L bag and another one a 70 L bag. So, if I do it anyway, it’s to give you an idea.
These are only approximations, which are based on an average hiker in average hiking conditions (water supply possible at least once a day, no special equipment, non-extreme weather conditions, not too bulky equipment, balanced sharing between teammates, etc.).
For example, this table is not valid for a person hiking in the high mountains and requiring mountaineering equipment, for a person hiking with children, for a person practicing ultralight hiking, etc.
Yes, but what do I put in it?
If you have followed well, you must first gather all the rest of the material before looking at the volume of the backpack. But you are probably wondering what to put in your backpack. To give you an idea, you can download the list of material that I offer on the blog. If you are interested in a reduced list, you can take inspiration from the contents of my bag on the GR20.
Volume is not the only criterion for choosing a hiking backpack, but it is an important criterion. I have already seen some people with a bag that is too small and more material hanging outside than material inside. As far as I’m concerned, I made the mistake of the bag is too full and filled up completely. Maybe you’ve already been fooled too?
If this article helped you, don’t hesitate to share it with your friends. Because if they choose a bag that is too small, you could find yourself carrying some of their equipment…
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