The Best Size of Backpack for a Day Hike

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Let’s say you’re about to head out on a day camping trip. You’ve made your plans, invited a friend or two, gathered all the supplies you need. You’re ready to go on this adventure but you just lack one thing: The right kind of bag to bring.

You head to the mall or your local outdoor shop and stare at the rows upon rows of backpacks. Which one should you get? What is the perfect day backpack for your hiking trip? What features should it have? How much should it be able to carry?

Before you become overwhelmed by all the choices and different options and features, worry not!

Here are some things to consider when shopping for the perfect day backpack as well as some options that are available.

We’ll take a look at the different daypack features, the fit of a daypack on your body, and your destination and activities, and hopefully, by the end of this, you will have narrowed down your choices so you can get the daypack for your upcoming hiking adventure!

Daypack Features

Some features are quite important, when picking a new day backpack for your next hiking trip.

Below we’ll walk through the most important features, and what to have in mind.

Frame Type

A backpack with a frame
A frame helps stabilize the backpack, and is great if you want to bring along some gear on your day hike.

There are different kinds of frames when it comes to backpacks. Most day backpacks have an internal frame that helps support the weight of what you’re carrying with you. Some frames are made of plastic, giving the backpack a lightweight structure. Others are sturdier, as their frame makeup is made of aluminium rods. The heavier the frame, the more sturdy and durable it is, and is able to carry heavier weight.

Check out the different kinds of internal frame backpacks. Don’t forget to see if the size is what you’re looking for!


Day backpacks that can carry 20 liters or less are better for activities that require you to be light on your feet, such as running, road biking, and some shorter hikes. They are compact and small and provide just enough room for your essential hiking gear, including a light jacket, some energy bars, water, and a few personal items.

For backpacks that can carry 20-30 liters, these are your trusty companions if you’re going on a longer trek, mountain biking, or running a longer distance. You can even use them when you go on a short trip. They feature more pockets and extra space for you to put more clothes, food, and other hiking gear you might need.

Day backpacks that are able to hold 30-40 liters are actually the more preferred option for hikers. There is enough space to carry an extra set of clothes, food for the long journey ahead, and even things that will help you enjoy your trip, like a book or a camera if you are into photography.

Backpacks that are 40-50 liters are the biggest and are ideal only for hiking excursions that will require additional clothing and gear, such as mountain climbing, mountaineering, and non-summer hiking.


When choosing your daypack, you’ll want to take into consideration which of your items goes where in the pack. Most day backpacks have a “top-loading design” which means that items that you don’t need to access immediately go to the bottom of the pack.

Other backpacks have front access, where the main compartment can be accessed by a U-shaped zipper. This makes it easier to fully open your pack and access all the items that you have stored. You can rummage through your bag when searching for something, plus, they are good for light hiking and travel.

Hydration Reservoir

A backpack with a hydration container
A hydration reservoir holds plenty of water in a comfortable way, so you can stay hydrated on your hike.

Not all hiking daypacks have these, but if you are going on a trip, whether a short trek or one that will take a whole day, it would be good to consider getting a backpack that has a hydration reservoir. Hydration packs are specially made to transport water and make drinking while on a hike convenient and efficient. If you want a built-in hydration reservoir in a daypack that has enough space to carry extra clothes, some food, and other essentials, you should check out hiking hydration packs. They vary in size, from small ones for short hiking trips to big ones that you can use for overnight outings.

Daypack Fit

There’s not much sense in choosing a specific daypack, if it doesn’t fit you properly. Especially when hiking longer stretches, you seriously want a backpack that fits your body proportions. Below are some important things to consider, before settling upon a new backpack:

Torso Length

When trying on the daypack to see which one fits you best, you’ll need to see how it fits your torso. There are so many sizes of backpacks these days, from extra small to extra large, and the ranges vary depending on the manufacturer.

A way to check if the backpack is the right size for you is by trying it on and positioning the hipbelt so that the top of the edge is a finger width above the top of your hips. Once that is in place, check to see where the shoulder straps land on your back and shoulders. If there is a gap on your shoulders, it means that the daypack is too long for you. If the straps are a few inches down your back before they connect to the pack, they are probably too short. You should get one that fits comfortably on your shoulders, with the backpack high on your back, and is just the right size for your torso length so that you will have no difficulty moving around.

Waist Size

Man hiking with a day backpack
It is important to pick a day backpack, that fits around your waist as well as your shoulders and length of your torso. Most backpacks are adjustable, so make sure you try it on and do proper adjustment before going on your first hike.

Daypacks also vary in terms of hip sizes. While most of these are adjustable, they usually range from 20-40 inches. When trying on the daypack, you should try the waist strap too, so that you are sure that it is loose or snug enough to fit comfortably around your hips.

Pro tip: Wearing the waist strap helps distribute the weight of your pack to the hips so that your shoulders are relieved from pressure.


After you check out the torso length and the waist/hip belt, you should also check out the straps to make sure they fit comfortably and snugly on your shoulders. Shoulder straps should be hugging your shoulders, but not carrying the load, which should be on your hip belt.

Destination and Activities

Group of day hikers wandering through nature
There are plenty of destinations to choose from, if you’re going on a hike. Make sure you choose the right backpack for the right occasion.

Before you even choose what kind of bag to bring, you and your companions have to figure out where you are going to and what sort of trip it is going to be:


When going on a day hike, you will most likely need to bring the following items among many others: water, extra clothes in case of emergency, food, and a first aid kit. In cases like this, one backpack that will fit all is a must. You’re definitely looking for something comfortable and with support and with a capacity from around 15-30 liters. You’ll definitely want to get a backpack with cushioned straps and back ventilation as well.

Try looking for backpacks that hold some key features, such as a hydration compartment where you can put extra water, compartments for smaller items (this is where your phones, maps, compass, flashlight, and the like go), little hooks or straps that will let you carry trekking poles or ice axes, and side pockets for your water bottles, energy drink, or sunscreen.

Nearly all day backpacks are alike with their hydration reservoirs and water bottle packets on the sides. It’s up to you to choose in terms of torso size and the way it fits on your waist and shoulders. Check out the different kinds of hiking daypacks here.

Pro Tip: If you’re the type to carry around extra supplies like water and food, you’ll need to get a backpack that can carry 35 liters or more.


Small lightweight backpack for climbing
If your day hike involves climbing, a small and lightweight backpack is preferred.

If your day trip is going to involve quite a lot of climbing, you might want to look for a day backpack that’s slightly smaller than the one you would take if you were simply going hiking. The capacity of a day pack for climbing should be around 12-20 liters for you to be able to carry on multi-pitch routes with no difficulty. It should also have a narrow profile that will allow you to move well while climbing with your pack on.

When going on a climbing-hiking trip, make sure that your pack is comfortable to carry and consider a structure that can handle heavier loads. Climbing daypacks often include special features, such as ice axe loops, daisy chain for lashing gear, crampon patches, and more. They are also often made with reinforcements and heavier fabrics to help minimize damage from abrasion.

Some recommended climbing daypacks are the following:


If you’re going trail running, adventure racing, or even jogging over a longer distance, a small daypack is recommended to bring along to help carry your things (25 liters or less). The smaller the size, the better, as you will need to use all your energy to run.

It helps to use a hydration daypack so that you have an ample supply of water and don’t need to stop in order to take a sip. Running backpacks and small daypacks are also designed to limit jostling and its pockets are specifically positioned for easy access to food and water while you run.

Check out some of the backpacks that are lightweight and perfect for running:

Cycling and Mountain Biking

Backpacks and daypacks that are suitable for cycling and mountain biking feature a light and stable design, while at the same time, they can be a bit bigger than other backpacks to accommodate extra gear, clothes, and bike tools. The ideal size for this is somewhere between 20-30 liters. Most cycling backpacks feature an internal organizer and zipped outer pockets where you can store some of your personal items.

Make sure that your backpack’s waist belt is something that won’t interfere with your pedaling. Ideally, your backpack should have both a chest strap and a waist strap as well as venting in order to cool down your sweaty back. It would also be good to choose a hydration pack instead of a regular backpack, so you have a reservoir for water and can drink from it without having to stop and unload your bag.

Check out the different kinds of cycling hydration packs here.

Whether your hiking will be a simple one half day or whole day trek, or one that will take you climbing, running, and possibly even cycling, there are different daypacks that you can try out as you look for the one that will meet your needs and make your adventure exciting, fun, and easier!

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