Osprey Atmos/Aura 50 vs 65: Which size pack is right for you?

As most of you know, I'm a huge fan of Osprey backpacks and talk about them a lot (full list at the bottom of this post). 

...especially about the Atmos/Aura line. 

...and especially about the AG 65. This is why I recommend it as the best multi-day Osprey backpacking backpack out there. 

I often get asked about the Osprey Atmos AG 50 vs 65 and the Osprey Aura AG 50 vs 65 (women's counterpart). So here's my comparison.  

In summary: 

If you'll be doing a fair amount of backpacking trips longer than 2 nights, I recommend the 65-liter versions (bonus: the larger pack features two extra front pockets). 

What's more: the top-notch construction of Osprey's Atmos/Aura series is probably a little overkill in the 50-liter sizes. This is why I recommend the Osprey Stratos 44 for men and the Osprey Kyte 48 for women in packs in the 40-50 liter size range. 

If you'll be backpacking Europe, Australia or South America (or any other place) for weeks/months at a time, then I strongly recommend the 65 L version of the Atmos AG (men) and Aura AG (women). You'll love the two extra front pockets as much as the additional 15 liters of volume.

You must have a GOOD reason to get the 50 L option. Some say the more space you have, the more you'll pack. But I don't think this is necessarily true for most of us.

This is why I'd only recommend the 50 L option over the 65 L option to those who won't be backpacking for anything longer than a couple nights (and three at the very most). 

What are the differences between Atmos/Aura AG 50 and 65?

Yes, the most important difference between them is the volume difference: 50 liters vs 65 liters - but this isn't the only difference.

As you can also see in their manual here [PDF], you also get 2 extra front pockets with the AG 65 options of both Atmos and Aura - which in the end make more of your items readily available. This is a lifesaver on longer trips.

Volume: How to decide?

Here's the way I look at it:

• 50 liters is considered as the sweet spot for backpacking trips up to 2-3 days.
• 65 liters is sufficient up to 5-6 days, or almost a week if you tend to pack very little. Then again, if you're an ultralighter, you should probably check out my Atmos vs Exos comparison rather than this post.

Now, putting this rule of thumb aside, I always recommend opting for a backpack with around 10-15 liters more volume than you think you'll need.

Two front pockets: How important are they?

Granted, these pockets become more important when you're on a longer backpacking trip (or pack more stuff for any reason: trips with kids or pets, winter hikes, etc.). The entire point of these front pockets is to make more of your items readily available.

If you think you might need a pack with even better organization, check out the Aether AG 70 and how it compares to the Atmos AG 65 (or Aura vs Ariel for women).

At the end of the day, not having to dig through your entire inventory when you need an item stuck somewhere in the middle of your pack will save you a lot of time and frustration.

So the more you pack, the more you'll benefit from the front pockets. 

Is anything else any different?

No. Comfort, adjustability and ventilation are all the same and top-notch between the 50- and 65-liter versions.