Please Note: This Page Is In Progress

This means, among other things, that:

  • Some of the content is not fleshed out, so you should not read more into things than exactly what is there.
  • Some sections might have things marked as “TODOs” (e.g., questions or things that must be done). These TODOs should not be taken to be representative of truth in any respect, and indicate areas that need more research and thought. If you have particular knowledge in things related to these, you can help! (Please see: contribution guidelines).
  • There probably will not be any section that pulls everything together in an easily understandable way.

This does not mean that:

  • I am not firmly convinced of the veracity of all the content currently published. If I am not sure of something, I don’t push it to the website. (This doesn’t mean that I won’t ever change my positions if I come to learn that I am in error, but that I strive, as much as possible, to only push content to the website if I am absolutely certain that it is true).
  • This page cannot be helpful to you in its present form. If you are aware of the limitations of the current state, you may find this page helpful long before I officially publish it.

Optimization Variables

TODO: determine best order to go through variables. Alphabetically?

TODO: decide if having some sort of weighting scheme would be appropriate, or if leaving it to individuals and their circumstances would be better.

Sweat Management

When wearing a backpack for an extended period of time, especially on hot and humid days, it is best to have some way to minimize pack contact with your back. Failing to have such a system leads to excessive sweat buildup, and, over time, smell.

There are two main ways that this accomplished. The first way, which is probably most common, is to use vented mesh backing on the pack, with airflow channels. This has the advantage of being cheap and easy to design. The second way is using a frame system to keep the pack almost entirely off of your back. This is much more involved on the design end of things, and much more expensive as well (since frames are made out of materials like aluminum and carbon fiber), but works better overall. See below a a further discussion of frames.

Weight Distribution System

As discussed above, frame systems can be designed in such a way that they keep the pack off of your back, helping prevent excessive sweating. However, their main purposes lie elsewhere.

A well designed pack frame prevents what is known as “rounding out,” which is when oddly shaped items in the pack cause the back of the pack to bulge, causing a reduction in contact points. Overstuffed packs without frame systems to prevent rounding out can be uncomfortable to wear, since the majority of the force can end up distributed over a very small area. This is especially noticeable if the pack is worn during activities such as cycling, when the contour of the back tends to encourage less contact to begin with.

A well designed pack frame can also take almost all the weight off of the shoulders and redistribute it downwards. Anyone who has worn a heavy (e.g., 25 pound or more) pack for an extended period of time without a frame system has probably experienced muscle soreness and tension from having large downward forces concentrated over the shoulder region. Frame systems help prevent this.

An effective weight distribution system also requires a waist belt. Hiking packs typically have big cushy waist belts to spread out the load. Unless you are carrying really heavy loads, however, most reasonably broad waist belts will do. If you can manage to find a belt with more padding, all the better.

Carrying weight on your hips is much less tiring overall, and requires less core strength to maintain a healthy posture. Given that most people have weak cores (from a combination of too much sitting and not enough exercise), this is a bigger advantage than immediately apparent.

Chest Straps

Chest straps should not be the primary weight-bearing straps, since waist belts do this much more effectively. However, chest straps are still useful for locking the pack in place and preventing shifting, particularly during more strenuous activity.

It is best if the straps are adjustable in both tightness and positioning on the chest. Women with a large bust may find chest straps difficult to use if they are poorly designed and not very adjustable. I personally prefer chest straps that distribute the weight over a larger area than a single horizontal strap (as is the norm); a single strap can get uncomfortable and restrict breathing. For an example a better designed chest strap, see Aarn Pack’s “X-Flow Straps” on their accessories page.

Dynamic Straps

While straps that allow for multi-axis movement are extremely rare on most production packs, they make a lot of sense for people that do anything other than walking around with their backpacks. To my knowledge, Aarn Packs is one of the only (if not the only) company that consistently designs packs that allow for completely unrestricted movement.

The general idea with what I have termed “dynamic straps” is to have your pack glued to your back with a waist belt and chest straps, but have movement in all directions be natural, without resistance. This is accomplished by straps that can expand and contract as necessary, not through elastic necessarily, but through a “slider” system that can store unused strap length when not needed.

The degree to which this variable matters will obviously depend on your use case for a pack.

Front Balance Bags

Balance bags are again almost entirely unique to Aarn Packs. The general idea is to put dense, heavy items in two bags attached to front straps to balance weight on the back and get the weight distribution in line with the body’s center of mass. You can see some of Aarn Pack’s rationale here. This data should be taken with a grain of salt since it is being used for marketing purposes, but the theoretical basis makes tons of sense, and it wouldn’t surprise me to see most of the claims here verified over time.

It makes sense for the balance bags to be split since they obstruct vision less this way (you can look down between them), and they make taking the pack on and off less cumbersome than a single larger balance bag. Split balance bags have the disadvantage of not being able to carry very large objects, however.

In my opinion, balance bags are mostly the province of hiking packs, or packs used for other heavy weight-bearing activities. When we are talking about light loads, it’s not like the disruption to balance from altered COM is very noticeable, and the forces involved (especially if a properly designed frame and waist belt are being used) are not really big enough to cause strain. The added time and “fiddlyness” of putting the pack on and taking it off outweigh the potential balance benefits.

Strap Management

Straps should be adjustable to accommodate not only people of different sizes, but also winter jackets and the like. Adjustable straps tend to have a movable piece that slides up and down the length of the straps, meaning that the straps have “tails” that can flap around and get caught on stuff. This is pretty easy to fix, only requiring a couple of pieces to retain the loose strap bits. If the straps are excessively long and made out of a synthetic material, you can trim them down some and seal the ends with a lighter.

Strap management is especially important if you ever plan to use the pack on a bike or motorcycle. Taking a pack strap to the face at high speeds is not only painful, but also dangerous, since it could lead to a crash.

Hydration Bladder Compatible

Hydration bladders are not very good for everyday life. They are fiddly, hard to clean, and not useful when you are sitting down in a chair with a back (unlike a water bottle). However, if you are ever moving around for an extended period of time without taking your pack off, hydration bladders are extremely useful.

Therefore, it is good to have the option of using a hydration bladder, meaning that it is possible to store the bladder in a pocket while feeding out a tube with said pocket still sealed. You may be able to use “headphone holes” for this purpose on packs that are not specifically designed to accommodate hydration bladders.

Abrasion Resistant

Not much to say here. External abrasion/wear resistance (aside from having zippers that aren’t rubbish) is the single biggest factor in pack durability, so you want the best material you can get.

Full on 1000D Cordura and other engineering textiles aren’t really necessary for most people, but can be useful for people who are really tough on their packs or have a habit of falling off of motorcycles/bicycles at high speed.

Retroreflective Panels

If you are ever planning to use a pack on a bike or motorcycle at night, you really ought to ensure that it has retroreflective material. While it is easy to add this on your own with retroreflective tape, it tends to be more durable if applied in manufacturing (it won’t ever peel, for example).

Even as a pedestrian, it is good to have retroreflective material. The more you are out and about after dark, the more important this becomes.

Uncontroversial Look

I absolutely despise overpriced leather briefcases and the like. It’s such a stupid, inefficient method of carrying things, and the entire notion that you have to buy some special “professional” form of pack to fit in is mostly propaganda from the very companies that design these things. How they managed to hoodwink all of industry is beyond me. (Same deal with suits, uncomfortable leather shoes, expensive mechanical watches that are worse than quartz at keeping time…)

At the same time, I can understand why your boss might have a problem with digicam at a client meeting with sheltered businesspeople (for example). Sometimes tactical is not appropriate – some people will take you the wrong way (mall ninjas, etc.). Same thing goes for any sort of design that has associations with something controversial, like confederate flags, gay pride colors, etc.

Other than that? Go for it, in my opinion. I see no problem with people wearing hiking packs into the office, and hope it becomes more acceptable because it’s super practical. Hiking packs with swastikas, on the other hand? Best avoid.

External Water Bottle Holders

Having to fish around in a pocket for a water bottle isn’t the end of the world, but it is entirely preventable. I can’t think of a single good reason for a backpack to forgo at least one external water bottle holder.

Depending on the size of a pack and what you carry in it, the placement of water bottle holders can be important in determining how the pack balances. Water bottle holders tend to get placed on the sides of packs, which can be problematic since water bottles are pretty heavy relative to most things. It is best to either have a water bottle holder located centrally (like the Tom Binh Synapse 25), or to counterbalance a side-located water bottle with something else small but heavy that is useful to have quick access to. I personally balance side-located water bottles with the set of portable tools that I carry.

Zipper Pockets

Some people don’t mind the extra time that roll-top backpacks add to accessing everything, but I personally find them cumbersome. Roll-tops also don’t let you open them down the sides, which makes them less useful for finding things at the bottom of the pack. The also tend to be one-compartment affairs, which makes organization and quick access more difficult.

I like to have two main zipper compartments (one for electronics, books, and other things that shouldn’t get wet at all, another for my lunch, gym clothes, rain gear, and other things that can handle some moisture from hastily stowed rain gear), and at least one quick access pocket (for storing smaller items if I need to empty any pockets of my cargo pants for some reason).

If you are using a pack for a specialized thing, like hiking, roll-tops can work fine. You don’t need to access stuff very often when hiking (and can put frequently used items in balance bags). Roll-tops will be discussed again below when I talk about pack waterproofing.

Internal Organization

It is good if each of the main zipper compartments has a degree of internal organization. The back one should have a laptop/tablet sleeve, as well as a pouch for a hydration bladder (preferably). A mix of zippered and open pockets makes the most sense.

Such internal organization helps things always be in the same place (rather than scattered at the bottom of a big compartment). Consistency leads to speed when finding things.


There are four main classes of pack waterproofing: submersible packs, weatherproof packs, removable dry bags and liners, and pack covers. Each of these has distinct advantages and disadvantages.

Submersible Packs

Submersible packs are overkill for most people and circumstances. Submersible packs are made out of a material that is absolutely impermeable to water (generally some sort of TPU-coated textile) with high frequency welded seams and some fully waterproof opening and closing system. Submersible packs with zippers (like the Patagonia Stormfront) use waterproof zippers like the TIZIP (which are a bit more difficult to open and close but seal incredibly well). Some higher end roll-tops, like the Ortleib Velocity, are also submersible if you take the time to seal them properly. However, they have all the disadvantages of roll-tops mentioned above. Some dry bags used in hiking packs and the like are also submersible, but they are the fiddliest option of all, and not good for quick access. (For example, see Rockagator dry bags).

How long a pack can be fully submerged is variable. To my knowledge, the packs with waterproof zippers handle extended submersions best (they are actually fully airtight), but for quick-submersions, any of the above options would work fine. They would all make good boat bags, fishing packs, kayaking packs, etc. Packs that float get bonus points.

The biggest downside of these packs is that they tend to be quite pricey. Unless you know your pack might get dunked on a regular basis, weatherproof is sufficient for the vast majority of the population. Additionally, the waterproofing can make them more fragile overall (i.e., less abrasion resistant), but this does not necessary have to be the case. These sorts of packs also tend to be heavier overall, so if you don’t need the ability to fully submerse your pack, it’s probably best to go with a different waterproofing method to keep the weight down. Finally, since the waterproofing is built in, anything that compromises the waterproofing compromises the pack (there is not feature separability). This may not sound like a big deal (“just don’t compromise the waterproofing”), but it means that a simple accident can compromise a $300 pack.

Weatherproof Packs

This is what most packs mean when they say “waterproof.” While they lack some of the features that make submersible packs, well, submersible, they’ll handle basically everything else without batting and eye. Bicycle commuters and people who want to make sure their stuff stays dry favor these types of packs.

A lot of the startup companies and gear geeks target this type of pack (for example, Mission Workshop), so if you’re looking for a weatherproof pack, you’ve got plenty of high-end options. You can pick from zipper packs, roll-top packs, and even messenger bags, briefcases, and the like if that’s your thing. (In my opinion, backpacks are always superior). There is the danger of choice paralysis, so I would recommend setting a budget, doing some research, and just going with one. If you buy from one of the good brands that stand behind their products, you really can’t go wrong.

Weatherproof packs have the advantage of waterproofing at all times (unlike pack covers, which will be discussed below). Most of the packs in this category worth owning are rather bombproof, so they tend to last a long time as well.

In terms of disadvantages, they are still moderately expensive (some more than others), the waterproofing is still built in rather than separable, and they too tend to be heavier than their non-waterproofed counterparts.

Removable Dry Bags And Liners

Removable dry bags are pretty self explanatory. Put stuff you want to keep dry in the bag. Seal the bag. Stuff stays dry. Liners are basically the same idea except you attach them to the pack directly.

Some people make their own dry bags and liners with garbage bags and the like. This works fine if you don’t mind the hassle of closing such solutions. One can acquire weatherproof roll-top dry bags and liners that close more efficiently and quickly for not very much money.

Dry bags and liners have several advantages. They are really cheap. They can be replaced if you tear a hole in one without replacing your whole pack. They are interchangeable between packs (bags more so than liners). They let you use a pack with much looser tolerances and less expensive materials (a much cheaper pack).

However, I’m not a big fan of dry bags and liners. They do not keep water off of your pack itself, so even if your stuff stays dry, your pack will get waterlogged (adding weight, reducing durability, and reducing comfort if it has substantial contact with your back – this a bigger problem for non-synthetic packs that don’t have a DWR coating). They also add another step to accessing your stuff (this is the biggie), and tend to make internal organization much more difficult (though this wouldn’t be the case if some manufacturer wisened up and started adding internal organization to dry bags – i.e., this problem is not inherent, but a supply problem).

It’s the fiddlyness that is the dealbreaker for me. If you don’t open and close your pack very much, dry bags may be the cheap, easy solution you’re looking for. In everyday use, I just don’t like having to open more things if I want to get to something, and close more things when I’m done.

Pack Covers

I think pack covers are the best waterproofing solution for most people. I understand the draw of the “always-on” waterproofing of weatherproof packs (and my inner engineer likes the bombproof designs and overspec materials), but, strictly speaking, weatherproof are unnecessary. So long as you check the weather on your phone and/or look out the window to see if the sky is cloudy before you head out, a pack cover provides equivalent weather protection for a fraction of the cost.

Pack covers work best if they are specifically designed for the pack they are being used with – you won’t have bits sticking out or a bunch of extra material. This limits pack selection somewhat, but many good brands do offer pack covers for their packs. (Particularly brands aimed at cyclists and hikers).

Here is a brief list of some of the reasons why I favor pack covers:

  • You can use a high visibility pack cover with good retroreflective properties to have maximum safety when you want it, but without having to have these attention-grabbing characteristics all the time. You could technically do this with weatherproof packs too, but then it’s an extra expense that isn’t giving you anything else.
  • Pack covers won’t add any additional time to get to things except when you are using them. Unless you only put your stuff in dry bags when it looks rainy and take it out when it doesn’t, pack covers will always be less fiddly than dry bags.
  • They are relatively cheap, and can be replaced independent of the pack if they get compromised.
  • They allow for the external material of the pack to focus on a single design factor: abrasion resistance. By removing waterproofing from the equation, really durable packs can be bought for a fraction of the cost, since it is much easier to design a durable pack that ignores waterproofing. This follows the same logic as rain shells: they allow you to have really good specs per dollar in your other jackets (since these jackets don’t have to worry about waterproofing considerations, only other things like insulation), but give you full waterproofing when you need it.
  • They keep anything stored on the exterior of the pack dry, which is something that even weatherproof packs can’t do. Skates, skateboards, water bottles, and anything else you keep on the outside of your pack can only get waterproofing from pack covers.

In terms of disadvantages, poorly designed pack covers can simply not work, or come off too easily (particularly if you are riding a bicycle or motorcycle). Poorly designed pack covers can also let in a lot of water through the back of the pack (the part up against your back). If a pack doesn’t have a convenient place to store a pack cover, storage can be somewhat inconvenient. Finally, some people think pack covers look kind of goofy. If you are one of these people (or care what these people think), I suppose you should avoid pack covers.


Any packs that you are planning to use on bicycles or motorcycles should be as aerodynamic as possible. You don’t want a pack that will act as a sail in crosswinds (which can be quite dangerous), or a pack that will create a bunch of drag.

Generally speaking, smaller packs are better in both of these areas, so unless you really need a large pack, smaller packs are better for being on a bike or motorcycle.

Light Colored Interior

Since lighter colors reflect more light, they help you see down into the bottom of packs, making it easier to find stuff.

This is more important if you have a single compartment pack (like most roll-tops are). Packs like this tend to have a “black hole effect” whereby they eat things you put in them.

Low Weight

Light packs aren’t just for ultralight hikers. In general, the lighter a pack, the less it disturbs your center of mass, the less strain it puts on your joints, the less pressure it puts on whatever body part is bearing weight, and the more stuff you can comfortably carry. Lighter packs are better packs.

Easy To Clean

It’s great if packs are machine washable, but even better if they never get to the point of needing to be machine washed. Try to avoid fabrics that collect stains, dirt, and other various objects like seeds.

DWR finishes tend to make packs really easy to clean, and are cheap to apply to packs that don’t have them to begin with. I would argue that even if you use a pack cover for waterproofing, it’s still good to have a DWR finish since they make cleaning the pack exterior trivial.

High Quality Components And Construction

If I had a single word of advice about buying backpacks it would be this: do not buy a pack with bad zippers. On cheap backpacks, the zippers fail before anything else, every time. They don’t have to be self-repairing YKK zippers (e.g.), but they need to not be garbage. A zipper failure basically makes a pack useless, so take care to ensure that a pack’s zippers will last at least as long as the material the pack is constructed from. I would also suggest making sure that the zipper paths don’t have anything to get caught on, like a poorly placed lining or seam.

A similar cautionary note would go for other pack components, like buckles, snaps, etc., as well as pack stitching. If you want a pack to last for years of hard use, you need to check for double and triple stitching.

I would also recommend you check the interior materials. Some packs use really great exterior materials and then skimp on interior materials. If you ever plan to carry anything poky or abrasive, the interior materials should not be too cheap.

Carrying Handle

Every backpack should have one for picking it up. I can’t understand why some manufacturers don’t include them.

External Attachment Points

There has been a trend towards including a MOLLE on packs, which is a good thing. Having at least a few attachment points for things that ought to go on the outside of the pack (such as bike lights and trekking poles) makes good sense.

I am also a big fan of having a large exterior carrying mechanism, like the one on the Seba Small Backpack. This is usage-dependent (I skate, so having a place to conveniently carry them is important to me), but also useful to have in general. If you ever need to carry an oddly shaped object that wouldn’t do well in one of the pockets, or something too large for the pockets, having an exterior carrying mechanism can come in really handy.

My Picks

TODO: explain choices and reasoning

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