How to Choose Among the Top Osprey Backpacks for Trekking

by  Louis Otis
LAST UPDATED ON  2023-06-15
PUBLISHED ON  2020-01-03
I used the Osprey Aether 70L in the Semaphore Lakes area of British Columbia. It’s our top pick for longer treks, but would be overkill for shorter, weekend jaunts.

Your Guide

Louis Otis with helmet on mountain peak

Louis Otis

Wilderness Wizard

Looking to choose the right backpack for overnight hikes or treks? I’m here to guide you with my 10+ years of backpacking experience in all kinds of terrain, including climbing ascents and glacier travel.

You wear your backpack for hours and it is heavy, so it has to be a good fit for your body. Trekking with the wrong backpack could ruin your outing. This is a rather lengthy treatise about choosing exactly the right pack, but we think it’s worth our time and yours; your back and neck are worth it.

We’ll stick mainly to Osprey packs, which I use myself and are the most widely recommended brand (more on why below), but I will also mention a few other, cheaper options.

If you’re looking instead for a smaller pack for a mere day-long outing, check instead our in-depth analysis on choosing between Osprey daypacks.

Osprey Trekking Backpacks: Quick Side-by-Side Comparison of the Best Series

Click on the cute little green plus sign for more details on each series.

Overall Pros and Cons of the Osprey Brand for Trekking

There are other good brands out there, but I use and recommend Osprey because they have earned their reputation through years of making excellent trekking-specific backpacks. They have great engineering, useful features, and a diverse range of products to fit everyone’s needs.

FYI: Neither Osprey nor other brands have ever sent this site a dime. We buy our own packs outright, and our too-meager revenue comes from Amazon and other stores, meaning we can recommend any brands we like.

What’s to Love About Osprey Backpacks

The Drawbacks to Osprey — but They’re Not Weighing Us Down

Women’s vs. Men’s Osprey Backpacks: What’s the Difference?

Your trekking backpack is a critical piece of equipment you will wear for many hours. When you have so much weight on your back, it’s important to have a backpack that fits your physiology to increase comfort, avoid injuries, and make you want to keep doing the activity.

The gendered differences are not mere marketing; they allow you to choose a pack that is closer to your physiology and best transfer weight to the shape of your hips

Most lower-end brands make unisex backpacks. Some are decent and most are attractive pricewise. However, they have limitations in terms of fit at the shoulders, chest, or hips. When you try to fit both women and men, you aim somewhere in the middle and often end up short.

Typically, unisex backpacks tend to fit men better than women. My first trekking backpack was unisex and made by an outdoors retailer’s house brand, MEC. I still use it occasionally for day hikes in winter, but I have never taken it on an overnighter since purchasing my Osprey Aether. The quality simply can’t compare.

Osprey offers a line for men and one for women. Women-specific backpacks are usually narrower and have a smaller frame as women tend to be smaller than men. Shoulder and sternum straps are also contoured with the female upper body in mind. Finally, hip belts are efficient in transferring weight to the sometimes rounder hips.

Of course you can use this information to choose the pack to best match your body type, wherever you fall on the gender spectrum.

How to Measure Your Torso for Osprey Backpack Sizes

Measuring your upper body is important for choosing the right trekking backpack. Each series has different volumes available (40-70L, etc.), but then each of those packs also generally come in different sizes (S, M, L, XL). Getting the right size allows you to adjust the pack better, thus increasing comfort. Here’s what you need to do to get the right measurements:

  1. Locate the level of your hip bones
  2. Identify your C7 vertebra (it’s the bone that sticks out at the base of your neck when you bend your head down to your chest)
  3. Measure the distance between the two
  4. Use that measure to choose your size
Osprey’s guide for pack sizing.

We’ve included the size ranges (there’s a bit of overlap) for each size backpack in each series description below.

How to Pack your Osprey Backpack for Outdoor Trips

  • First, fill the bottom compartment. It’s usually advertised as being for the sleeping bag. You can put your sleeping bag in there or anything light and bulky, such as clothes, mittens, gloves, etc. You don’t want something heavy pulling you down.
  • Put the rest of your gear in the main compartment, keeping the heavy items close to your back. Make sure to pack carefully as opposed to stuffing everything in.
  • Use the compression straps to stabilize your load, removing air or dead space. Your pack will become less bulky and look more like a cylinder. This will be easier for you to wear as the pack will be more stable and the center of gravity closer to all ends.
  • When you put the backpack on, clip the hip belt so that it sits just on top of your hip bone and tighten it until you are comfortable. Make sure it’s not rubbing your skin and hurting you. Your hip belt is not a decoration, so use it appropriately.
  • The shoulder straps should be tight, but not putting too much weight on the shoulders. Otherwise, you will feel discomfort and risk injury.
  • The anchor points of the shoulder straps to the pack should be about two inches below your shoulders. Your sternum straps should be one inch below the collarbone and allow you to move freely.
  • Many larger backpacks have load lifters, a small strap linking the top of the back panel and the shoulder strap. Tighten them so the angle between the strap and the top of the back panel is roughly 45 degrees.

In a nutshell, make sure everything feels comfortable before going out. Remember that your hips are strong and should carry a fair share of the weight. When you are on the trails, it’s normal for your straps to loosen. Check your fit every few hours.

How to Choose the Volume of Your Backpack

An important part of choosing your backpack is identifying the right model and volume for your needs. Your options start at 40-45L and go up to over 100L. It’s not always easy to know which one is the right size for your gear, but I will cover a few questions to help you think about it.

What Will I Use the Backpack for?

What Is My Fitness Level?

What Equipment Do I Need to Bring?

Should I Get a Lighter Backpack?

The Top Backpacks for Regular Weekend Adventures

These packs will appeal to the majority of readers. If you do overnight hikes once in a while, sometimes pushing them to two nights, this is the section for you.

Kestrel 48L (Men) / Kyte 46L (Women): Small, Comfortable, Perfect for Trekking to Huts and Lean-Tos

Stratos (Men) / Sirrius (Women) 36L: Smallish, Tough, and Comfortable

Atmos (Men) / Aura (Women) AG 65L: Osprey’s Versatile Classics

The Top Lightweight Osprey Backpacks

If you want to reduce the weight you carry, don’t need a lot of space, and don’t mind simplicity, these packs are for you. They are also excellent for thru-hiking (end-to-end hiking in a single direction).

Talon 44L (Men) / Tempest 40L (Women): The Affordable Lightweight Packs

Exos (Men) / Eja (Women) 48L: The Luxury Lightweight Packs

The Best Osprey Backpacks for Longer Expeditions: Aether Plus 70L (Men) / Ariel 65L (Women)

The Osprey Aether Plus 70L

I recommend the Aether Plus 70L/Ariel 65L to support heavier loads. These packs are a bit heavy, but they haul heavy weight like few others. They also feature an anti-gravity suspension system for increased stability and comfort.

The Aether Plus/Ariel is available in smaller and bigger sizes, but I recommend the 70L/65L. The other sizes are good as well, but if you are interested in a smaller pack, look into the Atmos/Aura AG above instead. And the average backpacker won’t need more than about 70L. If that is not enough, you are bringing too much gear!

I frequently use my AetherPlus on overnight hikes. I often carry over 45 pounds, either my overnight gear plus my climbing or wife’s equipment. I have yet to feel discomfort and the pack always has good breathability. It is also durable and barely has a scratch after having taken some abuse in all seasons.

The Osprey Ariel 65L

There is plenty of storage and the organization of the compartments makes it easy to reach practically all your gear without having to go take your pack apart. I’m able to fit all my camp gear in the bottom compartment. There are plenty of loops, pockets, and straps for technical equipment. I use the front mesh pocket for wet equipment I want to dry.

The top lid is removable to reduce weight or use as a small backpack. It is not very comfortable however, so it only works for short side trips. A flap jacket covers the pack when the lid is removed.

Torso sizes for the Aether Plus (men’s):

  • Small: 16-19 in / 40.5-48 cm
  • Medium: 18-21 in / 46-53 cm
  • Large: 20-23 in / 51-58.5 cm
  • Extra-large (70L model only): 22-25 in / 56-63.5 cm

Torso sizes for the Ariel (women’s):

  • Extra-small: 15-17 in / 38-43 cm
  • Small: 16-19 in / 40.5-48 cm
  • Medium: 18-21 in / 46-53 cm
  • Large (65L model only): 20-22 in / 51-56 cm

Wrap-up: And the Very Best Backpack for Your Outdoor Adventure Is…

The backpack you should get depends mainly on your objectives, the gear you carry, and your needs in terms of features and comfort.

If you target performance, want a very light but comfortable option, and can afford it, get the Osprey Exos 48L for men or Osprey Eja 48L for women.

If you backpack once in a while and want space, features, and comfort get the classic Osprey Atmos AG 65L for men or Osprey Aura AG 65L for women.

If you do long treks or activities that require extra gear, get a reliable workhorse: the Osprey Aether Plus 70L for men or Osprey Ariel 65L for women.

Get a pack that is sized right, allows you to bring everything you truly need, has a little extra room for safety gear — an extra layer for example — and fills up to a weight you are comfortable carrying for your planned distances.

Happy trails!

7 thoughts on “How to Choose Among the Top Osprey Backpacks for Trekking”

  1. Thank you very much, Louis! Your analysis in this article is great! It helped me make a choice between Telon and Kestrle48

  2. Hi Louis! Thank you for a great article. Just wondering if you had a chance to look into the new Aether models? They don’t have the Anti Gravity suspension anymore and seem to be more adjustable for finer fit. Saying that I feel there is a bit too much adjustment in them and for an average hiker might be a bit overwhelming to get the right setup. I am wondering what you think about this upgrade? I was keen to get one but after trying it on today the old Aether 70 felt more comfortable than the new 65 model. Perhaps the adjustments were not done right? Anyway if you have any feedback yourself that would be great!

  3. Andrian Bilici

    Great article and thanks for writing it down. Appreciate it a lot. However I didn’t figure it out yet what to choose. I am thinking between Tempest 40, Talon 44, Exos 48
    Which one will be more comfortable with maximum admitted load?
    Like very much Exos, especially the straps, but I think is overkill for me 48L.

    1. Hi Andrian,
      The Tempest is for women, so I’ll leave that one out.

      The Talon 44 and Exos 48 are very similar in terms of size and volume. The Talon is smaller and slightly lighter. The Exos has a similar shape but is about 10cm higher.

      Even though the Talon 44 has a weight capacity of up to 18kg, it’s only comfortable with a load of up to about 13kg (30 pounds). The Exos on the other hand stays comfortable with a load of up to 18kg (40 pounds).

      If you want maximum volume and weight capacity, go for the Exos. Be mindful that it’s about 10cm higher than the Talon.
      If you want the lighter, smaller, and cheaper option, go for the Talon.

      I don’t know what you will use it for, but the 48L Exos should not be overkill compared to the slightly smaller Talon.

      Hope this helps!

  4. Hello Louis and thank you so much for this article! I’m looking for a backpack to travel around Asia and South America, and your article really helped me.

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