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Backpack Guide: Sizes & Features Explained

Backpack Guide: Sizes & Features Explained

20.03.2024 | Hiking Buying Guides

From backpacking and hiking rucksacks to daypacks and bags for weekend trips, this guide will take you through the various sizes and common features to help you choose the best backpack for you.

Backpack Sizes

 Size  Capacity  Suggested Uses
Mini and Small Backpacks  6 -10 Litres Absolute essentials for fast paced activities
Day packs  10 – 30 Litres Essential small items for day hikes/city walks
Medium Backpacks  30 – 50 Litres Essential equipment for
longer hikes
Large Backpacks  50 Litres + Lots of equipment for camping/expeditions

Backpack Size Guide

Large Backpacks: 50+ Litres

Best For: Travelling, Backpacking, Expeditions.

Inca 80L

Inca 80L

Carrion 65L Rucksack

Carrion 65L

Tor 65L

Tor 65L

Traveller 60L 20L

Traveller 60L + 20L Backpack

A large rucksack is ideal for anything from an extended hike (which will include camping) to backpacking around the world. These backpacks are designed to be able to hold a substantial amount of kit and will have plenty of pockets for storage. Large rucksacks may also contain a detachable backpack.

A 65 Litre backpack, is well suited for trekking and is a popular choice for those taking part in expedition award schemes.

If your trip will be for one week or more, a 70 or 80 litre backpack is highly recommended.

How to pack a camping backpack?

You may be wondering how to pack such a how to pack such a big backpack for camping effectively. Take a look at our top tips below:

  • Start with items that you need less often, this would be items like pillows and sleeping bags.
  • Then add your heaviest items, these should sit close to your back to help with balancing the weight and in turn helping you feel less tired for longer. Light items can then go next to them, away from your back.
  • The top of your bag should contain all the essentials you regularly use, like your torch and snacks. It’s a good idea to keep your first aid kit in this position too. Hopefully you won’t need to use it, but if you do, you’ll thank yourself for putting it in easy reach.

Medium Backpacks: 35 Litre to 50 Litre

Best For: Overnight Trips, Camping Trips, 3 day hikes if packing light.

Ventura 40L

Cargo 40L

Pheonix Extreme 35L

Phoenix Extreme 35L

Inca Extreme 35L

Inca 35L


Medium sized rucksacks (often between 35 and 50 litres) are designed for multi-day use and for carrying heavier loads than daypacks. Most of these backpacks will have all the features of a daypack but with additional padding, pockets and fixing points for all the extra equipment you’ll need for a longer trip.

A medium sized backpack, would be ideal for those thinking of an overnight trip. If you pack light, a 40 or 50 litre pack would also be sufficient to hold your clothing, tent and sleeping bag for a 3 day hike.

Daypacks: 10 Litre to 30 Litre

Best For: Day walks, hikes and expeditions, commuting.

Not Suitable For: Weekend trips that require you to carry sleeping bags and other camping gear.

Pace 30L

Pace 30L

Inca 18L

Inca 18L

Bolt 18L

Bolt 18L

Darwin 12L

Darwin 12L


Daypacks can be any size between 10 and 30 litres and as the name suggests are primarily designed for one day trips. They are well suited to walkers and hikers who will be spending the day outdoors. Some daypacks will be hydration compatible so a hydration system can also be carried in the pack.A 30 litre backpack, is also suitable for weekend trips as they will easily accommodate spare clothing, water, food and other essentials. However, if you have to take sleeping bags and other camping gear, it’s likely you’ll need a larger rucksack.

Mini and Small Backpacks: 6 Litre, 8 Litre, 10 Litre

Best For: Days out, Kids and Sports.

Not Suitable For: Carrying large heavy loads or for extended trips.

Animal Recycled 10L Dry Backpack

Animal Recycled 10L

Trek 8L

Trek 8L

Espirit 8L

Esprit 8L

Walklet 6L

Walklet 6L


Small rucksacks are very versatile and are as suitable to shopping trips as they are for day trips or walks. An 8 or 10 litre backpack will easily accommodate a packed lunch, drink and some packable waterproofs.

Their compact size also means they make great kids backpacks. An 8 or 10 litre backpack makes the ideal school bag whilst our 6 litre backpacks are the perfect size for younger children.

Choosing The Best Backpack For You

One of the main factors to consider when choosing the best backpack or rucksack for you is how big it needs to be. This will depend on what you plan to use if for (eg. everyday bag or a week-long trip) and how much you need to take (the bare essentials or kit for an overnight stay).


Backpack Litre Capacities

People often ask how big is a 65 litre rucksack? Or how much can I fit in a 30 litre backpack? Backpacks are measured by the total capacity of all of the pockets in litres. Essentially, you’ll be able to fit 30 litres of gear in a 30 litre backpack. This however might not mean a great deal when you are trying to decide if a rucksack is big or small enough for your needs. It’s often easier to look at the actual measurements (perhaps even compare to a bag you already own), to get an idea of how big the backpack is.

What is a Rucksack?

A rucksack is very similar to a backpack but the phrase is often used to describe larger bags or those designed for travelling. However, in the UK both terms are used interchangeably.

The Fit

It’s important that your backpack fits correctly so you can carry it in comfort. This will depend on your build and back length (not your overall height). Most backpacks will come with adjustable back straps (bigger backpacks are also likely to have adjustable chest straps) to ensure your backpack fits securely and comfortably. If the backpack sits too low, even when adjusted, it is too big for you.

You may decide to pick a backpack that comes in women’s fit. This is a backpack that has all the same features as a regular fit but is designed with a shorter back system for a smaller torso and with less space between the two shoulder straps to fit onto your body better. You will find that the shoulder straps are cured to accommodate a woman’s bust and the chest strap will be positioned above it. Women’s fit also has a narrower hip belt and shoulder straps. Our Ventura 40L, the Tor 65L, the Inca Extreme 65L and the Carrion 65L are all available in women’s fit.

Check out our How to Fit a Rucksack guide for more information.

Common Backpack Features

Backpack Features

Compression Straps

Compression straps (adjustable straps which can be found on the top, side or down the front of backpacks) can be pulled tight to reduce the volume of the pack and to minimise movement of items within.


Back & Chest Straps

Adjustable straps are essential for ensuring a good fit. Chest straps ensure the pack is secure and help distribute some of the weight. For larger rucksacks you can adjust the height of the straps depending on the length of your back. Straps will often be padded for added comfort which is especially important for heavy rucksacks.


Hip Belt

Around 70% of the weight of the sack will sit on your hips. An adjustable hip belt is a common feature on medium and large backpacks as it helps to secure the bag around the hip area for added support and load transfer.


Pockets & Compartments

Multiple internal and externals pockets are useful for organising and separating contents. Internal security pockets are essential for stashing valuables whilst side mesh pockets are ideal for holding water bottles.

To help divide contents further, some larger packs may have a completely separate bottom compartment with zipped access that is closed inside with a drawstring. Larger rucksacks might also include a hip belt and lid pockets for easy access to important and frequently used items.


Rain Cover

A rain cover (tucked away in a handy pocket) is useful for covering your backpack to stop the contents getting wet in the rain. If your backpack doesn’t come with a rain cover you can buy one separately.


External Clips & Hooks

External clips and hooks can be used to attach equipment to your backpack, especially useful for hikers and travellers. These include daisy chains (a strip of webbing loops), elasticated cords and walking pole hoops. Carabiners can also be purchased separately to attach additional kit to your Rucksack.


Reflective piping

If you plan to wear your pack in the dark, reflective piping will help you be seen.


Internal Frames

Larger backpacks may have internal frames to distribute weight and provide support to your hips to help you keep an upright walking posture.


Other features:

  • Air Flow back system (designed to promote ventilation)
  • Lumbar padding
  • Bungee cords for extra storage 
  • Walking poles loops
  • Hydration pack compatible
  • Internal laptop compartment

How to wash a backpack

Now you’ve picked your backpack and used it, it’s time to learn how to clean it!

1. Empty your backpack, checking all pockets and corners for any small items or dirt that may be lodged. If your backpack has a metal frame, remove this before washing.

2. Fill a bath or basin with plenty of lukewarm water. If the water is too hot it can cause the backpack’s colours to run.

3. Add a small amount of gentle detergent that is suitable for backpacks, this should be fragrance and dye free. Using a harsh detergent or fabric softener may damage the material of the rucksack, our Wash N Proof  is a great choice if you are unsure whether your regular detergent is gentle enough.

4. Scrub your backpack using a soft brush or a cloth, focusing on the areas that are particularly dirty. A toothbrush can be useful for any tough stains or for getting into those difficult to reach areas.

5. Allow the backpack to dry naturally. Try to hang the backpack upside down if possible, and make sure it’s 100% dry before storing it away.

If your backpack cannot be fully submerged, you can use a wet cloth with a small amount of detergent-free soap.

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