Cosm Vs Aeron Comparison: The New Kid and the Classic

Aeron and Cosm are Herman Miller chairs with great build quality and back support. So what are the same and difference between these two? Join FittingChairs to see our Cosm vs Aeron comparison.


Cosm vs Aeron: The story behind

Behind each invention of each ergonomic chair, there is always the story for that, from the idea to the designing process. So what is the story behind the creation of Herman Miller Cosm and Aeron?

Herman Miller Cosm

For the Berlin-based designers at Studio 7.5 – Carola Zwick, Roland Zwick and Burkhard Schmitz, their latest chair for Herman Miller is a design that creates a new reference point for instant, personalised comfort.

“You should have a chair that allows you to change postures as easily as possible.” Roland Zwick says. “You can only do that with a chair that is adjusted correctly, so we wanted to build a chair that does that part for you.”

Cosm’s new Auto-Harmonic Tilt in particular has been a goal they’ve worked toward for years. Studio 7.5 and Herman Miller perfected the self-adjusting tilt by inventing a complex, finely tuned mechanism.

“We like a product that is readable so that you can understand, even if you’re not a mechanic or an engineer, how you’re being supported”, Carola says.

The chair’s ergonomic design is further enhanced by Cosm’s Leaf Arms, the first of their kind.

Studio 7.5 was no less dedicated to its aesthetic appearance. With its continuous suspension and sculptural form, the chair appears as a single unified object, and not a collection of parts and pieces.

The German word for design is “entwerfen”, which roughly translates as “to throw”.

With Cosm, “throwing” led Studio 7.5 and Herman Miller to their most sophisticated design yet.

Herman Miller Aeron

Thanks to the extensive research from designers Bill Stumpf and Don Chadwick nearly 30 years ago, Aeron was designed for a wide range of body types.

Herman Miller Aeron’s launch was pioneering in the office furniture industry. 

This chair is an ergonomic revolution when it first hit the market in 1994 and quickly became a status symbol in offices around the world.

Then, in 2016, Herman Miller decided it was time to remaster the chair to keep up with 21st century living and the latest science.

“We updated the Aeron Chair, adding ocean-bound plastic to the body – all without compromising what makes it the best work chair on Earth.” – Herman Miller

Besides two great ergonomic office chairs, refer this top list of the best Herman Miller chair to have a hugely worthwhile investment!


Cosm vs Aeron: What’s the same?

Cosm Vs Aeron Comparison: The New Kid and the Classic

Herman Miller Cosm

The Cosm’s ergonomic design instantly responds to your body, movement and posture to provide natural balance and total support.

Cosm Vs Aeron Comparison: The New Kid and the Classic

Herman Miller Aeron

Ergonomic to the core, Aeron was designed for a wide range of body types.

As both chairs are manufactured by Herman Miller, there are certain to be some similarities.

Both Herman Miller Aeron and Cosm have a 12-year of warranty. You can request a full refund within 30 days as well.

The Herman Miller Aeron chair is designed with a unique pellicle mesh that is ultra-breathable.

The Herman Miller Cosm chair is a self-adjusting mesh chair with a focus on aesthetics and performance.

You can see that these chairs are constructed of mesh. They both offer incredible breathability and unbeatable comfort.

However, there are some noticeable distinctions. Keep reading the Cosm vs Aeron comparison to see the differences.


Cosm vs Aeron: What’s the difference?

So what’s the differences between Cosm vs Aeron?


The first aspect to compare between Cosm vs Aeron is their size.

The Herman Miller Cosm 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 are looking for a headrest with the Aeron.

If you have shorter legs, the Cosm could be a good choice since it has a slightly shallower seat depth.

The Herman Miller Aeron is able to accommodate different sized users by having three distinct sizes: A, B, C (small, medium, large). The B size will be perfect for most of the users.

The various adjustments on the Aeron will allow you to accommodate a much wider segment of users as well.

Build quality

The next difference in the Cosm chair vs Aeron comparison is the build quality.

The Cosm uses an injection molded polypropylene frame with an aluminum base. The plastic frame is excellent in quality and feels premium. It creates a level of flex to the chair that the Aeron can’t achieve.

The back of the Cosm allows you to twist side to side in the chair and the back follows your back. It is a cool feeling and can only be achieved due to the materials used in the frame.

The Cosm was designed with the build, the quality, and the aesthetics in mind.

The entire structure or every part of the Cosm chair is well built, from the rinds to the shape of the chair. And the overall color of the Cosm is very uniform.

The Aeron uses mainly powder-coated or die-cast aluminum in its frame and base. It uses the excellent Pellicle 8Z mesh while the Cosm uses a newer design called “intercept polyester elastomeric seat mesh”.


Adjustability is one of considerable difference between of Aeron vs Cosm office chairs.

Details, the Aeron office chair has many adjustable features including multiple recline positions, tilt options, height adjustment, backrest angle adjustments, armrests, and seat depth adjustability.

It has everything from the back support tension to its armrests adjustment, right down to the tilt control.

See how to adjust the Herman Miller Aeron in the following video:

On the contrary, the Herman Miller Cosm has no physical controls. The goal of the seat is to be able to adapt to your body instantaneously, without requiring manual adjustments. To know more about this chair, read our Cosm chair review!

Herman Miller designed the Cosm with a high degree of flexibility. They say that your feet won’t ever need to touch the floor, even when sitting in their chairs.

So when it comes to the ergonomic adjustability, the Aeron is the winner. The reason is clear; the Aeron offers all the bells and whistles, while the Cosm is the complete opposite. It’s made without any knobs, twists, and turns.

The adjustability is the biggest difference between the Herman Miller Cosm vs Aeron.


The Herman Miller Cosm is the first “passive ergonomics” chair that the world has ever known. When the chair catches your weight up to a certain point, it locks you in that fulcrum point.

The Cosm chair feels very comfortable. You’ll feel weightless when you’re sitting on it. The chair aims to understand your body without any adjustments on your part.

The comfort level of the Herman Miller Aeron is no doubt. The seat and backrest are so flexible that they support you no matter how you sit.

Not to mention, the material is very breathable.

A feature that stands out from this chair is the PostureFit technology. This design help promoting the natural curvature of the spine.

You can either raise or lower where the support goes with its back support adjustment.

Back support

The back support of the Cosm chair is great. The overall design of the backrest features more curves at the lumber as well as the top.

Cosm vs Aeron

This is the reason for the absence of lumbar support. The high back model includes a neck or head rest.

However, the Aeron chair features incredible lumbar and back support. Those who have lumbar or back issues will experience more ease in Aeron.

Cosm vs Aeron

But if you’re looking for the neck or head rest, it’s something that isn’t present on the Aeron. People who wish to have a neck rest will be into the Cosm more.


Cosm offers four armrest options, fixed armrests, leaf armrests, adjustable armrests, and no armrests. The leaf arms seem to be the most fascinating and desired.

Although they aren’t adjustable, the angles of the leaf armrests were designed to ensure comfort for everyone.

The mesh material allows the elbows to sink to provide better support. However, the mesh may be too rough on the skin.

On the other hand, the Aeron offers three customization options for its armrests. The standard ones do not incur any additional charges. But as the customizations increase, so does the cost of the product.

The three adjustable options are fixed, height-adjustable, and fully adjustable.

So, in terms of ergonomics, the Aeron owns the better armrests for sure.


Cosm vs Aeron: What’s customers say?

Let’s take a look at some reviews for Herman Miller Aeron vs Cosm from customers on Herman Miller store and Amazon.

Herman Miller Cosm reviews

See more Cosm chair reviews here.

Cosm vs Aeron

Positive reviews

A review from Lia L.: “Beautiful and comfortable.”

I work on the computer for long hours and I always have a hard time adjusting a chair, no matter what I try, something always feels wrong. I am not a tall person and I could never find a chair that was the right fit for me. I was a bit skeptical but decided to try the Cosm chair.

On the first day, I felt like there was some sort of adjusRead more about I work on the computer for long hourstment missing to make it feel right. After a couple of days, I got used to the chair and it’s not perfect! It’s hard to believe a chair with no adjustments can feel like this. It significantly alleviated my back pain and my posture is better.

I ordered my chair the leaf arm and to be honest, I am still getting used to it. The idea is great for people who don’t rely on the arms for typing, all I need is something to support my elbows. However, the arms are too far so I usually only use one at a time. While I really like how bouncy the mesh feels, it can be a bit harsh on the skin after a while (even when wearing long sleeves).

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Amanda K.: “Absolutely gorgeous chair!”

Beautiful colour, extremely comfortable. Perfect ergonomic chair-superior back support.

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Negative reviews

Christian K: “Great chair but those arm rests.”

The mesh arm rests are horrid if you intend to actually ever use them. Rest of the chair is fantastic.

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Steven M.: “Unacceptable!”

Ship dates inaccurate and not as advertised.
Multiple delays in the orders.
Wrong chair arrived.
Getting money refunded was time consuming and labor intensive.
Customer service department cannot fix simple issues like returning your money or providing delivery estimates on back orders.
The whole experience was a nightmare.

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Herman Miller Aeron reviews

Here are what’s customers say about the Aeron on Amazon.

Cosm vs Aeron

Positive reviews

Ismail A.: “A must have for office workers!”

When I was looking around for a new office chair I knew I needed to get the Herman Miller Aeron. Working as a software developer I sit for long hours at my desk and I need proper support for my back. At my last job, everyone was provided a Herman Miller Aeron (though it was not this newer model), and I fell in love with this chair. I could sit for 5 hours plus and not feel any pain or numbness in my back or legs. The support this chair provides is out of this world, especially for the lumbar. I am 6’2 200 pounds and this chair doesn’t have any issues supporting me and I feel like I am floating in it.

The features this chair provides are also fantastic. I especially love how I can adjust the back to force me to sit upright and close to my keyboard in perfect posture. To be honest, there is nothing like this. I’ve heard that some people don’t like the mesh cushion (which can be a preference thing), but if you do like it you cannot go back to any other ordinary office chair. You will feel the difference immediately. Going back to my desk, I actually look forward to sitting long hours in my chair.

This chair may be pricey, but the way I justify it, it’s like buying a new mattress. You don’t want to skimp out on something you utilize so frequently. If you work at a desk for long hours, you need proper support, else you can damage yourself in the long term. The benefits outweighed the cost for me and I don’t regret spending the extra dollars for this. If this chair does last me over 12 years like warranty states, its money well spent.

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Justin: “The only thing that fixed my lower back pain.”

Switching to working from home has caused me to not only be sitting more often, but to be sitting in my subpar desk chair. This has caused me to get lower back pain since it has no lumbar support and is not very ergonomic.

In my search for a solution to the problem I have tried 3 other chairs: Steelcase Leap v2, Herman Miller Embody, Autonomous Ergochair 2. All of these chairs were OK but had major flaws in comfort for me, especially considering the first 2 are very expensive chairs. The Leap and Embody both reclined too far back which caused upper back pain. The ergochair 2 was definitely kind of cheap in construction and was only ergonomic fully upright.

For me being kind of short and liking to sit upright the Aeron is the only chair that offers everything. And it is the only thing that has helped my lower back pain since lockdown.

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Negative reviews

Aaron Reed: “The chair will feel ok for a month.”

My work bought this chair for us when we transitioned buildings. It felt so much better on my tail bone due to the mesh fabric that I bought this one (the one I am reviewing) for my home office brand new. I alternate between this chair and standing at my desk periodically. What I found is it is causing mid-to-lower back issues for me. My back aaaaaaaches now due to the chair not having lower back support. The mesh fabric allows your lower back to roll to the back of the chair. The controls that should provide support to your lower back are very poorly built and actually put a little pressure above the lower back. It’s in the wrong spot. Don’t buy this chair. It’s way too expensive for this much back pain. Find a chair with lower lumbar support if you have a desk job.

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A. Cabrera: “Not worth the price.”

I own the Aeron B chair with all the bells and whistles. The construction is excellent, but after time the right armrest became wobbly, and I can not tighten or take about without ending the lumbar support wires, which are very hard for me to disassemble. The next thing is comfort. At first, it feels great, but after 2 to 3 hours, I start losing circulation on my legs, and I get a sharp pain on my tail bone. This is supposed to be an 8 hour plus chair. Nope, three hours at the max. Based on my own experience, this chair is not worth the money they are asking for. I am now using a chair pad and a neck support pillow to sit comfortably while I work long hours. For a chair at this price range, you shouldn’t have to do that or put up with pieces falling apart.

I understand that the Aeron chair is considered an industry-standard in offices, but at $1400, there are more cons than pro. To place a pad and have a shaky arm, I would have been better off with a $300 chair and assembling it myself.

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Cosm vs Aeron: Pros and cons


Herman Miller Cosm vs Herman Miller Aeron: Final thought

To sum up, these two Herman Miller chairs are truly some of the best ergonomic office chairs.

Comparing Cosm vs Aeron is really a tough task.

The Aeron is one of the classics, while the Cosm is the new kid in the market. Both chairs have different upsides and it’s up to each user’s needs.

If you’re looking for a highly adjustable chair that offers superior comfort and breathability, go for the Aeron.

If you’re seeking for modern beauty with an innovative smart ergonomic design, go for the Cosm chair.

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Hope that you can choose the best ergonomic office chair for yourself. Don’t forget to come back to FittingChairs for more information.

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