When Herman Miller first announced the Cosm chair, I saw it as a sort of evolution of the Aeron. But after actually using the Cosm I realized that the Aeron is still likely the better option for most people looking at high-quality mesh chairs. In the battle of Herman Miller Aeron VS Cosm I have to say that the adjustability and tried and true design of the Aeron just works better for most users. The Cosm may be a great option for occasional use like in a conference room or a home office where it is not used for long periods of time, but it is just too limiting to be a better pick than the Aeron.
That is to say nothing about the pure quality of both the Aeron and Cosm. The same insane attention to detail and solid, made in the USA parts, make both chairs in the top 5 best-constructed chairs around along with the Steelcase Leap, Steelcase Gesture, and the Herman Miller Embody.
The choice between the Aeron and Cosm should be easy. If you want full adjustability, go with the Aeron. If you want a cleaner aesthetic and the latest mesh technology, go with the Cosm. Just make sure you don’t go with the Leaf arms on the Cosm…
Still our go-to office chair: Herman Miller Aeron
There is a reason the Herman Miller Aeron is mentioned as top of the class all the time. The Aeron is comfortable, bomb-proof, and very adjustable so it can fit just about anyone’s body. And it looks great while doing it.
New kid on the block: Herman Miller Cosm
Interesting design but only for a specific customer. The idea of making a chair that does all of the adjustments for you is a bold one. And, for the most part, it works. But we really do miss some of the manual adjustments from the Aeron. The Herman Miller Cosm may be great for a very specific customer.
Specifications: Herman Miller Aeron VS Cosm
| Herman Miller Aeron | Herman Miller Cosm | |
|---|---|---|
| Height | 41″ (size B) | 40.25-51.25″ |
| Seat height | 16-20.5″ (size B) | 21″ (all sizes) |
| Width | 27″ (size B) | 26.7-28.9″ |
| Depth | 16.75″ (size B) | 26.7″ |
| Seat depth | 16.75″ (size B) | 15.4″ |
| Weight | 41 lb (size B) | 34.9 lb |
| Maximum weight | 350 lb | 350 lb |
| Seat material | Pellicle 8Z mesh | Intercept polyester elastomeric |
| Frame material | Aluminum | Polypropylene |
| Base material | Aluminum | Powder-coated or polished aluminum |
| Head rest available | Yes (modular) | No |
| Size(s) | A, B, C | Low, medium, high |
| Lumbar support | Normal, PostureFit SL | Not adjustable |
| Adjustable seat depth | No | No |
| Adjustable seat height | Yes | Yes |
| Back height adjustment | No | No |
| Arm rest height adjustment | Yes | No |
| Arm pivot adjustment | Yes | No |
| Recline | Yes | Yes (but no adjustment) |
| Recline back stop | Yes | No |
| Recline tension adjustment | Yes | No |
| Forward seat tilt | Yes | No |
| Casters available | Normal, carpet | Normal (nylon), quiet-roll |
| Assembly required | No | No |
| Warranty | 12 years | 12 years |
| Environmental rating(s) | Level 3 ANSI/BIFMA | Level 3 ANSI/BIFMA |
Size(s)
The Herman Miller Aeron is able to accommodate different sized users by having three distinct sizes (A – small, B – medium, C- large). For most, the B size will be perfect. But if you aren’t sure which one will work for you, check out our handy guide on how to pick the right size Aeron. Keep in mind that the various adjustments on the Aeron will allow you to accommodate a much wider segment of users as well.
The Herman Miller Cosm also comes in three sizes, but these all refer to the back height (low, medium, high). The high back version is an excellent choice for people who would generally be choosing a headrest with the Aeron. Think of it as an integrated headrest. If you have shorter legs, the Cosm could be a good choice since it has a slightly shallower seat depth.
Weight & weight capacity
Both the Herman Miller Aeron and the Cosm can hold up to 350 lb, which is just about the average in the industry. The chair’s weight itself is different though. The Cosm is a lighter chair at 34.9 lb VS the Aeron’s 41 lb for the mid (B) size. This is likely due to the choice of materials on the Cosm. It uses more polyamide and polyurethane in its design as opposed to the Aeron’s reliance on aluminum in the frame.
Materials
Speaking of materials, let’s get into what each of the beasts is made of. The Aeron uses mainly powder-coated or die-cast aluminum in its frame and base. Whereas the Cosm uses an injection molded polypropylene frame with an aluminum base. I wouldn’t say the Cosm is at all less durable though. The “plastic” frame is excellent in quality and feels premium. It also adds a level of flex to the chair that the Aeron can’t achieve. Literally, the back allows you to twist side to side in the chair and the back follows your back. It is a very cool feeling and can only be achieved due to the materials used in the frame.
These chairs are often compared because they both use a form of mesh for the seatback and seat. The Aeron uses the excellent Pellicle 8Z mesh while the Cosm uses a newer design called “Intercept polyester elastomeric seat mesh.” That’s a mouthful… In actual practice, these meshes are quite similar. The Cosm’s has a different sort of weave to it, with small holes as opposed to the Aeron’s more classic horizontal weave. Both are incredibly durable and I can imagine the new Cosm mesh being just as good at repelling rips and tears as the Aeron’s.
Colors
The Herman Miller Aeron comes in quite a few color and material combinations now:
- Graphite frame / graphite base
- Mineral (grey) frame / polished aluminum base
- Mineral (grey) frame / satin aluminum base
- Black frame / polished aluminum base
- Black frame / Onyx Ultra Matte base (eco-friendly option using plastic waste)
If you are a gamer, the Aeron’s gaming chair version may be of interest. It includes a few extra adjustments that allow you to tilt closer to your monitor.
The Herman Miller Cosm on the other hand comes in what they call “dipped in color” styles. Essentially this means that the whole chair is uniform in color. It really is stunning and leads to a super slick look that is unlike anything I have seen in an office, chair. The colors are:
- Black
- Blue
- Gray
- Red
- White
Each of these appears matte in color and really looks great alongside the minimalistic design of the Cosm (only one adjustment lever). There is an option where it uses a white frame and mineral (light gray) mesh if that is your thing.
Adjustability
This is the main category that causes major problems for the Cosm. Its design intentionally removes manual adjustment except for a single lever for seat height. Instead, Herman Miller has made a chair that is supposed to automatically shift with your body and cradle it no matter what position you are in. It’s an interesting idea, but one that kind of falls flat in my opinion.
Lumbar/spine support
The Aeron has always been a great chair for back support. And when they redesigned it a few years ago and added the PostureFit SL premium back support, it really rocketed the Aeron to the top of my personal favorite office chairs. It expertly cradles both your lumbar and sacral and can even adjust these two elements separately.
The Cosm feels great on the spine even without manual adjustments. The shape of the back support is amazing in that it perfectly contours to both the lower spine and neck area. We especially like the high back version which extends to create a built-in neck rest. The problem here is that this support inevitably won’t be perfect for everyone. And without manual adjustment, you are kind of out of luck with the Cosm.
Back height adjustment
Both the Aeron and the Cosm achieve different back heights based on the size model you choose. The Cosm actually does a better job with this since the high back version truly is something that supports your neck (without the addition of a separate neck rest like the Aeron).
Other adjustments
Aside from the back height though, the Cosm simply doesn’t have any other adjustments. It relies on the Auto-Harmonic tilt and suspension system in the seatback to support the body. The result is a chair that is comfortable at first but becomes somewhat annoying in longer sessions.
The Aeron’s detailed lumbar support option, fully 4-way adjustable arms, seat angle adjustment, and tilt limiter just make it a much more pleasant experience. The one area I really missed when testing the Cosm was a tilt limiter or recline lock. Because none of this exists on the chair, you are always in a state of recline. I personally like to set a locked position to force me into better posture when doing long-term task work since I work from home. The Cosm becomes tiring to use after a while since you are fighting to stay upright all the time.
Comfort
Comfort can be a major issue with the Herman Miller Cosm. First, the mesh-based armrests are bad. I see what Herman Miller was going for with the hammock design of their “leaf” arms, but the mesh used is simply too abrasive to use for any period of time. I literally felt the mesh damaging my shirt and even scratching the skin on my elbows as I worked. Because of this, I highly recommend staying away from the unique leaf arms and instead opt for the adjustable arm option on the Cosm. But this kind of removes one of the unique features of the Cosm… Why not just get an Aeron with rock-solid 4-way adjustable arms?
The other big issue with the Herman Miller Cosm is the way they approach reclining. As mentioned above, I just don’t like not having the option to tilt limit or lock the reclining position. For this, the Cosm is vastly inferior to the Aeron.
Wheels
Both the Aeron and Cosm come in a choice of normal carpet caster or quiet roll multi-floor option. In my experience, these are both great and will not damage your floor or chair mat.
Headrest
As mentioned above, the Aeron can be purchased with an add-on head/neck rest. It is great, but it does add to the cost. Whereas if you purchase the high back version of the Cosm, it essentially has a built-in headrest. And it feels really great.
Durability
Aeron chairs have proven their durability over the years. You will easily find 20-year-old Aeron’s with zero damage on the secondary market. The frames, mesh, and mechanisms are simply rock-solid. The Cosm hasn’t had this same time to prove itself, but the materials used are equally impressive. The mesh may even be more durable than the Aeron’s Pellicle 8Z but only time will tell. In the end, if you are choosing Herman Miller, you are getting the most premium durability out there with USA-made parts that have been put to the test.
Resale value
Both of these chairs will retain great resale value since they are Herman Miller’s. This is because of their rock-solid construction and a no-fuss 12-year warranty.
Price
A base-level Aeron will be comparable in price to the high back Cosm. In our opinion, the high back is probably the best value in the Cosm due to its excellent back support. However, it is hard to justify paying similar prices for a Cosm when it is lacking almost all of the intricate manual adjustment that the Aeron has built-in. Because of this, I would say that the Aeron is still a way better deal.
Warranty
As mentioned above, Herman Miller has an amazing 12-year warranty on all of its chairs. And this is really a no-fuss warranty. They will cover all shipping costs and repairs for this full 12 years without any issues. I have owned several Herman Miller chairs over the year and have never once had to tap the warranty, but it is nice to know it is there if I need it.
Who is the Herman Miller Cosm made for?
When testing the Cosm I kept on wondering who the heck this chair was made for. It felt a bit like an Aeron but with the excellent manual adjustability removed. I think the Cosm may be a good pick for two main customers: (1) people buying chairs for conference rooms or (2) people who have home offices that don’t work for extended periods of time.
The comfort issues with the mesh on the Cosm and its constant reclining position are deal-breakers for me in my task-oriented application when I work from home. But I can imagine having a fleet of Cosm’s in a conference room would be really nice. Sitting for an hour or so would be totally fine in a Cosm.
But if you are looking for a truly full-featured office chair, the Aeron is still top of the pile when you are looking at mesh-based solutions. It remains to be my favorite overall office and the chair is what I use day in and day out.
Herman Miller Aeron VS Cosm: Conclusion
I’m sure you have figured out by now that I am no fan of the Herman Miller Cosm. Its lack of adjustability is a deal-breaker and the leaf armrests are objectively bad in comparison to the Aeron’s offering. If you don’t plan on doing long-term task work or just need an occasional chair, then the Cosm will be excellent. But for those looking for a flexible option for many different applications, the Herman Miller Aeron is simply a better office chair.