In the world of office chairs dominated by big names such as Herman Miller at the top, and a whole bunch of throwaway brands at the bottom, Sidiz is a breath of fresh air. Operating out of South Korea, the company is known for its mostly midrange office chairs with high end functionality.
In this review, we take apart their most popular offering, the Sidiz T50, to see how it stacks up as an ergonomic fabric office chair.
Sidiz Office Chairs Lineup
The Sidiz T Lineup comes in three models. The one we review here is the center one:
The Sidiz T50 and T80 are similar in features on paper, though the T80 is superior in most facets. The T80’s lumbar support is wider, the seat padding is thicker, the backrest tilting is more robust (advanced synchronized tilt), and the casters are urethane instead of nylon. As such it is also much more expensive.
The Sidiz T50 Air is better suited for hotter climates thanks to the mesh seat. Curiously though it removes the forward seat tilt and dedicated lumbar support features.
Assembly of the Sidiz T50

Assembly of the Sidiz T50 was reasonably easy with very few steps to get through. The only difficult step was attaching the backrest to the seat pan, which required more force than expected. This was a little difficult to control when supporting the weight of the fairly heavy seat.
Anyone advised not to lift heavy objects should get someone to help them assemble the chair.
Specs & Dimensions
To start, here are the specs of the Sidiz T50 chair.
Seat Width | 18.5” |
Seat Depth (Adjustable) | 18.3” to 21″ |
Seat Height Range | 17” to 21” from floor to top of cushion |
Forward Seat Tilt | Yes |
Backrest Height | 22” from seat cushion to top of chair |
Backrest Tilt | Tilt angle limit lockable to 5 angles (maximum 25 degrees back) |
Backrest Recline | N/A |
Tilt Tension Control | Yes |
Lumbar Support (Adjustable) | 2-way adjustability (up/down & in/out to change pressure on your back) |
Armrests (3D) | 3-way adjustability (up/down, pivot & in/out) |
Weight of Chair | 46 lbs |
Suggested User Weight | 130 to 275 lbs |
Suggested User Height | 4’9″ to 6’2″ |
Note: These numbers may differ from those stated on the manufacturer’s site but these are my measurements directly.
Quick Video Review
Features and Adjustability
The Sidiz T50 has a few noteworthy ergonomic features and adjustments.
Seat Adjustment
Firstly, the seat height can go as low as 15″ measured from the ground to the top of the seat cushions. This makes the Sidiz T50 great for short people that often find their feet dangling from regular office chairs. I can easily plant my two feet on the floor as someone who is 5’4″.
I also appreciate the waterfall seat edge and ability to adjust the seat depth on the Sidiz T50. Whether you’re short or tall, the 18″ – 21″ seat depth adjustment ensures the back of your knees will never brush up against the edge of the seat.

One of the defining features of the Sidiz T50 is the forward tilting seat function. Push a lever, and the entire seat tilts forward (and locks into place) at a slight angle from horizontal. I hadn’t realized how much I was tensing my neck, waist and back until I tried it and felt immediate relief in those areas. If you find yourself leaning forward often (such as if you’re short or have short arms), this feature makes the Sidiz T50 a good alternative to the Herman Miller Aeron that also supports a similar feature (but costs 4x as much).
Backrest Tilt and Lumbar Support
I like the tilting mechanism on the Sidiz T50, which offers granular control on how far the backrest rocks back. There are 5 thresholds up to 125 degrees max. These settings proved useful to me based on what activity I was doing, whether I wanted to tilt back and relax to watch a film or sit upright to type.
You can not recline and lock the backrest angle, sadly. Personally I don’t miss the feature much, but this is something to take into consideration.

The lumbar support on the Sidiz T50 is also worth mentioning. In a nutshell, it could be better. While you can control both its height and depth, its small size may not provide enough coverage for you, and can even feel protrusive when brought closer to your back. I have it at the loosest setting so it’s basically out of the way. If you need robust lumbar support, the Sidiz T80 is a better choice.
The backrest has a curved design that gives good support and matched the shape of my back comfortably. It does vary in width, with the widest area being the top at 18.5” and the tightest area being at the lumbar with 15”. Due to the slight curved inwards design on the edges of the backrest, this tightening may prove uncomfortable for anyone with a wider waist.
Other Features

Rounding up the list of ergonomic features on the Sidiz T50 is the 3D armrests. It can be adjusted up/down, left/right and in/out. I found them very easy to use and appreciate the notches on the height adjustment that helped me make sure that I was matching both sides. In terms of the left/right and in/out settings, there is no way to lock the position, though I did not have any issues with accidental shifting.
Note: The T50 Model that I tested does not come with a headrest. One can be purchased separately however.
Build Quality & Aesthetics

The Sidiz T50 is an attractive piece of furniture. Despite being predominantly plastic, it still manages to look sophisticated and even premium.
The chair boasts a GREENGUARD certification, meaning that eco-friendly, non-toxic materials were used in the build. It is also advertised as having been through rigorous quality tests conducted by BIFMA in the United States. The maximum weight capacity of the chair is a respectable 300 lbs.

One thing I love about the fabric seat is that it comes with a cover that comes off easily for washing. For users who are clumsy like I am, this feature can be a saving grace after accidental spills. For the average user, it is still a great feature that makes it easy to refresh the chair after continued use.
What I didn’t Like about the Sidiz T50
Despite the mainly positive impression so far, there are a few things I didn’t quite like about the Sidiz T50:
Firstly, as already mentioned, the lumbar support could benefit from being wider and softer.

The seat cushion is on the thin side. After sitting on it for a month, it has settled to about 2.5″ in thickness. It’s still comfortable, but if you’re looking for a plush seat, this isn’t it.
And finally, the biggest issue I have with the chair is that it rolls almost uncontrollably on hard surfaces. I have slightly uneven flooring in my office and found myself drifting towards the other side of the room. This means the Sidiz T50 is best suited in a carpeted room or on top of an office chair mat.
Sink or Swim?
Overall, the Sidiz T50 is solid enough to get a recommendation from me, especially as a good productivity or study chair.
Yes, the seat padding and lumbar support are areas that could be improved upon. The good news is, unless you need extra TLC in your butt or back, this is a comfortable chair with high end ergonomics.
The 5 step tilt limiter, seat depth and forward tilting adjustments are all practical features that actually improved the way I feel when I sit. As a shorter person (5’4″), I also loved the low 15″ minimum seat height setting. The chair should be comfortable for people between 4’9″ – 6’2″.
- Robust seat height range for even short people
- Waterfall seat edge and depth adjustment
- Forward seat tilt similar to the Aeron Chair
- Fabric seat cushion can be removed and washed
- Eco friendly materials
- Rolls around uncontrollably on hard floors
- Seat padding on the thin side
- Pressure from the lumbar support can become uncomfortable when using the pressure adjustment feature
- Assembly may require two people
Ben says
Great review! I’m 5’4” and I’m interested in the T50, but your seat height measurements differ from what the manufacturer lists on Amazon. They list the lowest setting as 18.1 inches vs your measurement of 15 inches. Is yours measured whilst compressing the cushioning? Hence the lower 15” height measurement?
Also the depth of 18.3 inches still sounds too deep compared to something like the Aeron size A. Is this depth mitigated by the significant waterfall sloping?
Thanks
Jon Muller says
15″ is around when your body is sitting on the seat cushion and compressed. Michelle (the reviewer) is actually 5’4″ as well actually.The depth is actually 18.3″, mitigated perhaps by 1″ based on the way most people sit.
You can watch how the T50 actually fits someone your height in our video review here: https://www.youtube.com/watch?v=JAgk1xP3SBI&t=2s&ab_channel=ErgonomicTrends
LL says
5’4″ is average for a woman, not short. It would be nice if more companies made chairs like the T50 that can be adjusted to be comfortable for the majority of women.