What Rucksack Do I Buy

What Rucksacks Do I Buy?

Looking for a new rucksack? There is a very wide range of to choose from. It is important to get one that fits correctly, here are some ideas on how to choose a rucksack. We will talk through some common design features and things you might want to take into consideration to help you purchase the right one for your needs.


One of the first things you should think about is how big you want your rucksack to be. Are you just going out for a few hours or will you be spending a week walking and hiking the mountains. What will you need to carry in the rucksack? 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 will be able to fit in 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 is 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. In this guide we will take you through the various backpack sizes and what activities and situations they are most suited to.


It is important that your backpack fits you 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 and vice versa.


  • 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.

  • 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 secured and help distribute some of the weight of the pack. For larger rucksacks particularly you can adjust the height of the straps depending on the length of your back. Often straps will be padded for added comfort- especially important for heavy packs.

  • Pockets & Compartments

Multiple internal and externals pockets/compartments 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 hip belt and lid pockets for easy access to important or frequently used items.

  • Reflective piping

If you plan to wear your pack in the dark, on a night run or hike for example, reflective piping will help you be seen.

  • Rain Cover

A rain cover (tucked away in a handy pocket) is useful for covering your rucksack to stop the contents getting wet in the rain. If your rucksack doesn’t come with a rain cover it is possible to buy rain covers separately.

  • External Clips & Hooks

External clips and hooks are useful for attaching gear you may need often to your backpack- especially useful for hikers and travellers. These include daisy chains (a strip of webbing loops), elasticated cords and walking pole hoops.

  • Internal Frames

Larger rucksacks may have internal frames to distribute the weight of the bag and support it on your hips as well helping your keep an upright walking posture.

Mini/Small Backpacks- 6, 8 and 10 litre

Small backpacks are very versatile and are as suited to shopping trips as they are for day trips or walks. An 8 or 10 litre pack will easily accommodate a packed lunch, drink and some packable waterproofs. The compact size also means they are great for kids. An 8 or 10 litre backpack makes the ideal school bag whilst 6 litre backpacks are the perfect size for younger children. Mini backpacks are also popular with runners, cyclists and skiers as they are just the right size for stashing snacks and extra layers.

Daypacks- 10 – 30 Litres

A daypack (or daysack) can be any size between 10 and 30 litres and as the name suggests they 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 may also be suitable for weekend trips as it will easily accommodate spare clothing, water, food and other essentials. If however you have to take sleeping bags and other camping gear it is likely you will find the backpack to be too small. Smaller daypacks are also suitable school bags and are ideal for commuters.

Medium Backpacks- 35- 50 Litres

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 rucksack 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.

Large Rucksacks- 65L +

A large rucksack is ideal for anything from an extended hike (which will include camping) to going on long expeditions. These rucksacks are designed to be able to hold a substantial amount of kit and will have plenty of pockets for storage. A 65L rucksack is well suited for trekking and is a popular choice for those taking part in the Duke of Edinburgh award scheme. If your trip will be for one week or over a 70 or 80 litre backpack is highly recommended. For added versatility you may wish to choose a rucksack that has a day sack attached- ideal for when you reach a base for your kit and then just need to pack light.

Rucksack Size Chart