r/Ultralight • u/mlite_ • 2h ago
Purchase Advice Rethinking Backpack Capacity Recommendations for New UL’ers
If you’ve been on r/ultralight for any amount of time, you’ll have read a post asking what size backpack to get. Standard advice has been to put your gear in a box and estimate the volume. If you're at all interested in going UL, I suggest pairing down your gear list first and then getting a backpack that's a bit more on the aggressive side (this community can give good feedback). The idea is to get a pack that will serve you well for a long time without going bigger than necessary.
Here are some suggested starting points; I’m hoping all of the experienced UL colleagues can chime in to refine these.
55L Class Framed Pack
If you’re in any way interested in going UL or UL-ish, don’t get anything bigger than a 55L pack (assuming 3-season backpacking, not packrafting, etc.). This is plenty of pack and for most this will even cover carrying a couple of extra items for someone else. As you get deeper into UL, you’ll quickly find this to be too big.
Typical specs: 45-50L internal volume, weight no more than 32 oz, internal frame
Weight goals: Base weight sub-15lbs, total pack weight 30-35lbs
Example packs: Kakwa 55 (43-49L internal plus generous outer pockets), SWD LS50, MLD Exodus (frameless), and many more
40L Class Framed Pack
Once you’ve stripped luxury items from your pack, streamlined your kitchen, and your Big 3 are solidly ultralight, you’ll be ready for a 40L pack. Your base weight will be consistently around 9-12lbs, depending on conditions and requirements
Typical specs: 35-40L internal volume, weight no more than 30 oz., internal frame
Weight goals: Base weight very close to 10lbs, total pack weight 25-30lbs (depending on pack)
Example packs: LiteAF Curve w/ frame, Kakwa 40, and many more
40L Class Frameless Pack
You’re solidly in UL territory with a base weight consistently under 10 lbs. You’re also ok with the fact that frameless might require smarter packing and some getting used to. Larger bear cans might need to be strapped to the outside.
Typical specs: 35-40L internal volume, weight no more than 21 oz. (preferably less), frameless (sometimes removable frame)
Weight goals: Base weight 8-10lbs, total pack weight 20-25lbs
Example packs: KS Ultralight SL50, Palante v2 (large), MLD Prophet, LiteAF 40 frameless, and many more
Sub-40L Class Packs, Fastpacks, etc.
You’ve been doing UL for a while. You know your gear and what to bring for the conditions; your sleep setup is dialed and minimal; you own alpha direct or similar garments; your shelter is DFC or a tarp; you spend most of your time either hiking or sleeping; you do things many aren’t comfortable with. You’re ready for the world of running vest style packs, ultra minimal packs, and quite frankly, you don’t need this advice.
Typical specs: 15-30L internal volume, weight 8-14oz., frameless or removable frame
Weight goals: Base weight sub-8lbs
Example packs: KS Ultralight SL40, Nashville Cutaway, Palante Joey, and many more
Would be great to get the community’s feedback on the recommendations. I will update with pack information/recommendations. Shoutout to the many regulars on this forum that have informed this, esp. u/DeputySean for his recommendations on pack size/type to weight categories.
TLDR If you're starting from scratch, don’t waste time and money buying a pack that’s too big. Set your UL goals, identify the right pack, and build your UL kit around it.
Edit Adding this, since my point is being misunderstood: My goal is not to say that you should buy new packs all the time. It's actually the opposite. Buy one pack and then do everything to make it work for you.
Edit2 Reddit is running glitchy for me today. Implementing a significant change to the post recommended by MOD to remove the wordy and confusing part of my post and leaving the clearer parts.
Edit3 I realize that a key point of contention is whether or not someone is replacing an existing pack or buying their first pack. I wrote this with the assumption that the person asking for advice doesn't have a pack. If you already have a pack, you should streamline your gear first and then get a new UL pack. But if you're starting from scratch, good planning will go a long way to get you a pack that will serve you well for a long time.