FlexiSpot ClassicRiser (M1, M2, M3, M4) Review

The benefits of working while standing have been clearly established, but purchasing a standing desk may seem like a big step.

Maybe you truly enjoy using your current desk or it could be that buying a new desk is not budget friendly. Either way, another solution that allows you to work while standing is standing desk converters.

A standing desk converter or a standing desk riser is a device that you can place on top of your usual office desk to convert it into a standing workstation.

Place your monitor on top of the standing desk converter, raise it up to the perfect height for you and voila! You can now stand while working on your computer.

Like most ergonomic furniture, there is a variety of standing desk converters to choose from. In this article, we focus on the FlexiSpot ClassicRiser.

This is a height adjustable desk riser that comes in 4 different versions, M1, M2, M3, or M4.

Let’s start by looking at the pros and cons. Then, we go into the nitty-gritty features of the FlexiSpot ClassicRiser and take a detailed look at this product.

FlexiSpot M1 M2 M3 & M4 Reviews

Overall Rating: 4.5 out of 5 stars (4.5 / 5)


Pros & Cons


  • X-lift vertical height adjustment.
  • Stability
  • Smooth dual gas spring motion
  • Adjustable with one hand
  • 4 models of different sizes and colors
  • Large, removable keyboard tray
  • 4 models of different sizes and colors


  • High(ish) lowest height setting
  • Keyboard tray sticks out

What users like and dislike about the FlexiSpot

As outlined above, there are plenty of great features that the FlexiSpot possesses. As with any product, there are a couple of small issues that would definitely not be dealbreakers but worthwhile taking a look at. Let’s dive deep into each of the features mentioned above.

Vertical height adjustment via X-lift frame

When it comes to standing desk converters, there are two popular types of frames – X-lifts and Z-lifts. Z-lift frames can be found in desk convertors that lift up and out, like the popular Varidesk Pro Plus 36 Standing Desk Converter.

The FlexiSpot ClassicRiser standing desk converter has an X-lift frame. These frames move the worktop straight up and straight down. Unlike the Z-frames, there is no horizontal movement. It keeps the workstation within its own footprint.

X-lift frames have several advantages over the more common Z-lift frames. Most importantly, it saves space.

FlexiSpot desk converter vertical lift
The vertical lift of the FlexiSpot’s X-frame makes it a great desk in tight spaces.

If your desk is located in a small cubicle or backed against a wall, you will need a standing desk converter that moves straight up. In fact, quite a few reviews explicitly mentioned how the FlexiSpot desk converter is a great choice for small spaces.

Not only that, an X-lift converter is generally less wobbly than a Z-lift converter. As you raise your desk from sitting to standing, your monitor may not teeter-totter as much.

With a Z-lift frame, you would need to carefully consider the weight distribution of the items on each tier of the standing desk converter. This is not the case with the FlexiSpot ClassicRiser. Users have consistently praised its stability, even with multiple monitors on the work surface.

That being said, do be careful with your fingers! The height adjustment handle for the FlexiSpot ClassicRiser is close to the gaps in the X frame, and there are a couple of pinch points that you need to be aware of.

Multiple work surface options

There are 4 models available and these mainly differ from one another in size. The smallest of all is the M1 model. Its desktop dimensions are 26.8 inches by 23.2 inches and the keyboard tray has a length of 26.8 inches.

The M2 model is wider. The depth of the desktop remains 23.2 inches but the desktop width is increased to 35 inches. The keyboard tray length is maxed out at 34.4 inches.

The M3 model ramps it up even further. To support a larger weight capacity, the desktop dimensions are the biggest on the M3, at 46.9 inches by 23.2 inches. The keyboard tray is 34.4 inches, just like the M2.

The M4 model is somewhat in between the M3 and the M2 in terms of size. The desktop is sized at 41.3 inches length and 23.1 inches in width. The keyboard tray remains large at a length of 34.3 inches.

The following diagram from the FlexiSpot official website shows you the differences between the models more clearly.

FlexiSpot model comparison

Which model to choose?

Well, the answer to that boils down to your needs. If all you need is space for a standard sized monitor and a cup of coffee, the M1 model should suffice. In fact, the M1 is able to support two smaller monitors as long as the screen sizes are less than 24 inches.

If you need a larger work surface to support multiple large monitors and other equipment like speakers or printers, one of the larger models may be a better choice.

If you do decide to go with the larger M3, don’t forget to measure your desk before placing your order. It has to be large enough to support the M3’s footprint.

Interestingly, the FlexiSpot M2 at 35″ wide seems to be the most popular size and model.

Whichever size you choose, there are four colors available – black, white, river walnut or mahogany.

Removable keyboard tray

We love the keyboard tray that comes with this standing desk riser!

First of all, it has extra-deep dimensions at 12.2 inches. This gives you enough space to fit in an ergonomic keyboard, your favorite wrist-friendly mouse (check out our ergonomic mouse buying guide), a mousepad and still have enough room left over to move your hands freely.

The width of the keyboard tray varies between the models. The smallest tray has a length of 26.8 inches (M1) and the largest measures 34.4 inches in length (M2 and M3).

There is one major drawback to be aware of. It is not possible to slide the keyboard tray entirely under the desktop. It sticks out by a significant amount.

Luckily, it is completely removable and user reviews have mentioned that it comes off easily.

When you don’t need to use the keyboard, just take away the keyboard tray to free up some valuable space.

You can see in the following video just how much bigger the FlexiSpot’s keyboard tray is comparing to most traditional standing desk converters.

Adjustable height range

By using this desk riser, the height of your monitor can be raised from 5.9 inches to a maximum of 19.7 inches. This is the same across all models.

The height range refers to the height of the monitor platform, not to the keyboard platform. When you are in a seated position, the keyboard will be flush against your desk so it only creates a slight height increase for your hands.

If you are small, you may find that having monitors raised almost six inches while seated can be a lot, so you could consider a desk with a lower minimum height.

In saying this, the FlexiSpot’s lowest setting actually slightly lower than that of the Fully Cooper which is considered our favorite standing desk converter.

If the FlexiSpot is too high for you, we recommend the Varidesk Pro Plus 36. This is a good alternative for shorter people as it only raises the height of your monitors by 4.5 inches at the minimum.

The FlexiSpot standing desk converter may suit taller folks, but it depends on the height of the desk. If your desk is 31 inches in height, you can be 6 feet 5 inches tall and still use this desk riser comfortably.

Within this range, 12 height settings are available. You are bound to find one that suits your body. However, if you have a slightly lower desk of 28 inches, the standing desk convertor will only work if you are shorter than 6 feet 1 inch.

Any taller and you may find yourself stooping uncomfortably. Ultimately the highest height of a desk converter depends also on your current desk.

To reap the full benefits of good ergonomics, your desk, monitor and chair need to be at the appropriate height. Not sure if the height of this standing desk converter would suit you? We have an article on correct desk heights to help you out.

The good height adjustability means that this desk can be used with under desk accessories such as treadmill desks and bike, as seen in this video:

Dual gas spring mechanism

Adjusting the FlexiSpot ClassicRiser standing desk converter is easy. The single handle design allows you to control desk height without much effort through the dual gas spring system.

For example, if your desktop has the maximum 35 lbs of items on it, it would take you only 13 lbs of force to raise the desk to a standing position.

With the help of gravity, lowering the desk is even easier, as it only requires a mere 3 lbs of force.

Manual height adjustments are acceptable to most people and hence, spring powered desk convertors make up most of the market.

However, if you wish to make it even easier, there are electric powered standing desk converters. For example, the Electric DeskRiser is a highly recommended electric model and it only needs a push of a button to raise the desktop.

Weight capacity

3 of the 4 models available (M1, M2 and M4) have a maximum capacity of 35 pounds. This is a generous weight that should be enough for the average user.

Just in case your gadgets are on the heavier side, consider the M3 model as it supports weights of up to 44 pounds.

According to reviews of this standing desk converter, packaging and shipping are straightforward.

It arrives covered with foam in a well-packed box and putting it together is easy with a simple one-step assembly. Just take it out of the box, place it on the desk, put the removable keyboard tray into place.

As the desk riser itself weighs 50.6 pounds, you may need an extra set of hands to help you set it up on your desk.

Final thoughts

A standing desk converter is a step in the right direction towards a healthier workstation, but it is only the beginning.

One great accessory to add would be a monitor arm. Luckily for you, FlexiSpot has a fantastic promotion at the moment for a free adjustable monitor arm.

Overall, this is a well-built standing desk converter that is ideal for small spaces. The desktop is highly customizable in terms of size and colors, so you can choose the best model to fit your needs.

On top of all that, throw in the free monitor arm and you’ve got yourself a good deal.

For more ideas on other standing desk convertors worth purchasing as well as a brief buyer’s guide, check out our article on the best standing desk converters.


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Dr. Praveena Asokan
Dr. Praveena Asokan

Dr. Praveena Asokan, MBChB has a background in medicine, having graduated from the University of Leicester before working in various hospitals. Her additional experience as a medical researcher helped her transition to a career as a writer, and she now enjoys researching and writing on a number of health-related topics.

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