Introduction (Guide to the Guide)
This guide is broken into two key sections:
- Guiding principles for what you want out of an ergonomic keyboard
- Different types of keyboards
The first section is intended to help you assess the ergonomic value of a particular keyboard. The idea here is to help give you the “tools to fish”, rather than the fish directly.
Many articles online list the ergonomic benefits of certain keyboard types without relating this to underlying principles. This section is trying to give you an understanding of what some of these principles are, so you can know what to look for yourself.
The second section gives a tour of different keyboard types and what the options are in terms of design features. We try to explain the ergonomic benefit of different features, as well as give concrete examples of different keyboard models using each feature.
We also identify some “bells & whistles” features that are less important from an ergonomic point of view. This is to help you separate the wheat from the chaff when deciding on a keyboard.
The intended audience for this guide is people who are suffering from or looking to prevent discomfort associated with keyboard use and are planning on upgrading to an ergonomic keyboard.
Please note that I’m not a medical professional so none of the ideas here constitute medical advice. It is the result of my personal research and experience. I would encourage anyone having any health issue (RSI or otherwise) to seek medical advice as needed.
Guiding Principles: Good Typing Posture
When using a keyboard, there are a few positions that increase strain on our muscles and tendons. Let’s go through some of these and principles that help us avoid them.
Minimise wrist extension or flexion
Bending the wrist “up” or “down”, known as wrist extension and wrist flexion, is one motion that can place extra strain on your wrist and forearm.
These two movements place additional stress on the muscles and tendons of your wrist. They can also put extra pressure on the narrow passageway on the palm side of your wrist, known as the carpal tunnel [1].
Wrist extension and wrist flexion as relevant to keyboard use are explained well in this video:
See the sections later in this article on concave keywells and keyboard positioning. These will help you understand how this principle can be applied when selecting keyboards to buy.
Minimise sideways bending of wrist
Bending the wrist to one side or the other, known as ulnar or radial deviation, are other movements to avoid where possible.
As with extension and flexion, these movements put extra stress on the wrist [1] and may lead to issues with nerve agitation or impingement over time.
See the section later in this article on split keyboards for an example of a design that mitigates this type of wrist movement.
Avoid sustained forearm pronation
Forearm pronation occurs when your palms are facing down and flat on the keyboard:
This is the standard position used for typing on a traditional keyboard. When sustained, this position can put pressure on the forearm muscles and tissues, restricting blood flow to the wrist [2].
In turn, this can lead to fatigue and in some cases Repetitive Strain Injury (RSI).
See the section on keyboard “tenting” for a design feature that combats this.
Avoid Arm Reaching
Reaching too far to the side for your mouse can put too much strain on your forearms, neck and shoulder.
Instead, you want your forearms to be roughly parallel and shoulder width:
Your arms shouldn’t be reaching too far forward either. See the section on keyboard position below.
Minimise Fingertip Impact and Movement
Traditional keyboards typically require a higher “activation force” for a keypress to register, compared to the right ergonomic alternatives.
This means you need to “bottom out” the key before it registers, increasing the impact on your fingers and adding to fatigue quicker.
You’ll want to look for keyboards that attempt to minimise impact force. See the section below on mechanical switch types for some discussion on this.
The section on thumb clusters also show how keyboard layout can be used to intelligently distribute the load across fingers.
Reducing finger movement is another useful ergonomic mandate. Again, the section below on thumb clusters is a good example of a design feature that helps with this.
In terms of typing habits, we also discuss keyboard layouts that can dramatically reduce unnecessary movements.
Consider Customizability
Finally, you’ll want to think about how easily your keyboard can be customised to suit your particular needs.
If you’re a bigger or smaller person, you’ll want a keyboard that can accommodate this.
For example, a completely split keyboard may be a good choice, since it lets you adjust the distance between the keyboard “halves”. This means you can ensure your wrists are resting roughly shoulder width apart and makes sticking to the above “guiding principles” easier.
Similarly, you may want a keyboard that lets you adjust the degree of tilt or “tenting” to match the size of your hands and width of your shoulders.
What You Use: Types of Computer Keyboards And Their Benefits
Form Factor
With respect to ergonomics, the first and arguably most important way to categorise keyboards is their form factor.
What I mean by this is the physical shape, size and layout of a keyboard. Keep reading for a tour of the main physical design features relevant for ergonomics.
Split Design
Many ergonomic keyboards sport a “split” design, whereby each hand has its own separate keywell area.
In this design, the keyboard is split into “halves”, with roughly half of the keys clustered to the left for use by the left hand and half on the other side for the right.
What this does is allow the wrists to remain straight and neutral whilst using the keyboard.
This is in contrast to traditional keyboards, which have all the keys “clumped together”. Such an arrangement requires the user turn their wrists inwards when positioned over the home row:
When in this “bent in” position, the wrists are under ulnar deviation. As discussed in the “guiding principles” section, research suggests this can contribute to wrist discomfort and carpal tunnel pressure [1][3].
There are two main types of split keyboards: fixed split and adjustable split [3].
A fixed split design simply separates the keywells onto either side of the keyboard, which is still the one connected unit. Each key grouping is at a fixed distance and cannot be fully detached.
While this can work well, the main issue is this keyboard type can’t easily be customised to suit a particular user. So, if you’ve got particularly broad shoulders, or deviate from normal body proportions in some way, this keyboard type might not be ideal.
Some examples of fixed split keyboards are the Kinesis Advantage2, the Microsoft Sculpt and the Microsoft Surface.
To address this, adjustable split keyboards are also available.
These normally come in the form of two fully detachable halves, allowing you to position each key grouping for maximum comfort.
They often also provide the ability to adjust the tilting or “tenting” of each keyboard half.
Great examples of adjustable split keyboards include the Kinesis Freestyle 2 and the Dactyl.
Concave keywells or flat
Traditional keyboards have a “flat” design, where all keys are placed on the same level and are at the same height.
One ergonomic alternative to this is to arrange the keys in a concave or curved shape, as seen here in the Kinesis Advantage2 (which is, by the way, my current keyboard):
This reduces finger movement to hit the keys (finger extension). It also allows the fingers to naturally sit below the back of your hand, reducing wrist extension and strain on the wrists [1].
Thumb clusters
Another important design feature to consider in keyboards is the position of key “high frequency” keys. Specifically, control keys like “ENTER”, “SPACE”, “CTRL”, etc.
Traditionally, many of these keys are awkward to press or require excessive finger movement to hit.
Some ergonomic keyboards address this by moving the main control keys closer to the thumbs in special “thumb clusters”.
This allows the load to be transferred from overworked fingers onto the thumbs and makes for a more comfortably typing experience for a lot of people.
Examples of keyboards that do this are again the Kinesis Advantage2, the Dactyl and the ErgoDox EZ.
Ortholinear vs staggered key columns
Another feature you can compare keyboards on is how keys are organised vertically.
In an ortholinear layout, keys are organised into vertically aligned columns:
This is in contrast to the traditional staggered layout:
An ortholinear, or columnar, layout reduces unnecessary sideways movement of your fingers as you type.
Put another way, ask yourself this: when you extend your finger, does it go sideways? No!
The bright spark who first came up with this layout recognised this and decided to stack keys on top of one another.
Tenting
As discussed earlier, leaving your hands “flat” on the keyboard (forearm pronation) can stress the muscles and tissue of your wrist.
Some ergonomic keyboards address this through “tenting”, a design feature whereby the hands can rest in a more neutral position during use.
Typically, the thumbs will lie on an elevated area on the keyboard, forming a “tent” shape when viewing the side profile of the keyboard:
Tenting can either be built into the board at a fixed angle, or it can be achieved through an adjustable tilt, as in the ErgoDox EZ.
Tenkeyless (no numpad) / Compact
Another way to compare keyboards is by the presence or absence of the number pad.
Keyboards without a number pad are known as “tenkeyless” or compact keyboards. The major benefit of this design is it greatly reduces the distance you have to reach for your mouse.
With a traditional keyboard, this reaching out can force your shoulder into excessive abduction.
This places strain on your shoulders, forearm and neck.
If you’re experiencing right sided pain in any of these areas, a tenkeyless or compact keyboard may be a good choice for you.
The main downside is entering numeric data without the number pad on tenkeyless keyboards is more awkward. If your job entails heavy numeric data input, this option may not be suitable for you.
Keyboard Switches
Keyboards can also be categorised based on their switch type. The switch is the component used for each key to register key presses, usually by activating a circuit when the key is sufficiently “pressed”.
There are a variety of switch types, each with different properties. The choice of switch type affects:
- Tactile feedback (the feedback given that a key has registered); and
- Pre travel (how far the finger needs to push before the key is registered)
As we’ll see, these two factors have some impact on ergonomics. In this article, we’ll only cover two important switch types, but be aware that there are a range out there. Click here to see some of the other options.
Rubber Dome Switches
The most common type of switch for mass market keyboards is the rubber dome switch. You’ll find it in most laptop keyboards, Microsoft keyboards and Logitech keyboards.
This switch type relies on a mushy “rubber dome”. When depressed by your finger, a circuit is completed and the key press registers. This is what it looks like:
This switch type is cheaper to produce. While usable for general use, it tends to be lower quality than some of the spring based alternatives.
The shelf life is generally lower and there is usually less tactile feedback. What this means is you normally need to “bottom” out the key to feel that it has registered. As a result, there is extra impact force and pre travel distance, which can add up over time.
Mechanical Switches
Mechanical keyboards use a switch mechanism based on a spring and are typically higher quality.
There are three subtypes of mechanical switches:
- Linear. These provide consistent resistance when pressing down
- Tactile. These provide extra physical feedback (a “bump”) when the key activates, allowing you to detect earlier when a key has registered.
- Clicky. These provide both tactile feedback and an audible click sound when a key press registers.
From an ergonomic perspective, tactile and clicky mechanical keys are good because they prevent the need to “bottom out” each key press. This minimises key press impact.
This is a helpful video that demonstrates each type of mechanical switch:
One major brand that makes these switches is Cherry. The Cherry MX line is a very popular variety of mechanical switches (I currently use Cherry MX browns myself, which feel fantastic… although I do find them a little on the loud side).
For more information on each type of Cherry MX switch, check out this video:
For an example of a mechanical keyboard, I’m going to again shamelessly link my review of the mechanical keyboard I’m currently using (the Kinesis Advantage2).
Note, the one I use is not cheap — there are cheaper mechanical keyboards out there! Mechanical doesn’t have to mean super expensive, although they do tend to cost more than your average rubber dome switch keyboard.
Other well known manufacturers of mechanical switches include Gateron, Omron, and Kailh.
“Bells & Whistles” (Less Important)
There are some design features that are less relevant for ergonomics. You probably don’t need a guide to tell you this… but I’ll put it in here anyway!
Let’s go through some design features that, in my humble opinion, don’t contribute much to ergonomics.
Sexy lighting effects
For some reason, gaming keyboards are BIG on all sorts of funky lighting effects.
As fun as this is, it will do nothing for your ergonomics. So don’t be overly swayed by flashy lights.
Wireless vs Wired
Whether a keyboard is connected wirelessly or wired does not really impact the ergonomics of your setup.
If you’re finding that being wired somehow forces you into an “unergonomic” position, then something is wrong with your setup. See the “Guiding principles” and “Keyboard position” sections to understand how things should be physically positioned in your workspace for maximum comfort.
Of course, there are practical “user experience” reasons to choose either wired or wireless options.
That said, as a former fan of wireless keyboards and mice, I’ve now come around to appreciate the wired option. There is no need to replace batteries, and generally wired options are more durable. When you’re dealing with a more expensive ergonomic item (i.e. Kinesis Advantage2), shelf life matters.
Projection Keyboards
One keyboard type that scores high on the “cool” scale, but low on the “ergonomics” scale is the projection keyboard.
What these do is project a virtual keyboard onto any hard surface:
They can then be used as an external keyboard during traveling or other situations where portability is important.
Unfortunately, the reality is these make touch typing without errors very difficult, and often require staring down at the virtual keys when you type (because you can’t use physical feel to gauge position) [6].
I recommend avoiding these.
What Will You Use It For
Outside of physical design features, how you plan to use your ergonomic keyboard is a factor as well in what model to pick.
There are two main usage scenarios:
- Everyday work. In this case, the keyboard will be sitting fixed on your desk, and so portability is less of a concern.
- On the go. If you need to work while traveling, or maybe out at a cafe, having something portable is more important. In that case, some portable ergonomic keyboards you might want to check out include the Atreus, the Kinesis Freestyle2, the Planck, or the Ultimate Hacking Keyboard.
If you want to compare the size of a few different keyboard models, you can check out this nifty web app I came across recently: https://jhelvy.shinyapps.io/splitkbcompare/.
You might also be getting an ergonomic keyboard to impress members of the opposite sex.
If that’s the case, I take back what I said about flashing lights — you’ll need more of them!
Remember though, whipping out an ergonomic keyboard on a date is kinda cheating. It makes you look too cool and the other person may have trouble resisting your charms. So there are some ethical considerations with doing this.
Flashing lights will also have more utility if you plan to make a keyboard ASMR video, like this one. If you don’t know what the hell I’m talking about, check out this video:
How You Use Keyboards: Typing Habits
In terms of ergonomics, what model of keyboard you use is only part of the picture.
How you use that keyboard is the other important part of the equation. The reason I wanted to mention this is it’s easy to fall into the trap of thinking “I’ll just buy this thing, and my problems will be gone”.
In reality, no keyboard will help if you have horrible ways of working and computer posture.
Check this post out for some information on typing posture and how to work more ergonomically.
Conclusion
Hopefully this article has given you a feel for what to look for in an ergonomic keyboard.
By first going through the “guiding principles” of keyboard ergonomics, I hope the guide helps you critically assess different keyboards instead of just accepting marketing claims.
I’ve also tried to illustrate different design features through several concrete keyboard models linked throughout. I hope these were useful references.
Obviously, there are tons of other ergonomic keyboards out there and the intention of this article was to talk more broadly about features and principles. So feel free to research other models!
If you find a particularly good keyboard, I’d love to hear about it — hit up my ‘contact’ page!
References
- ‘Effect of Wrist Posture on Carpal Tunnel Pressure while Typing’, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2649727/
- https://kinesis-ergo.com/solutions/keyboard-risk-factors/#forearm-pronation
- https://kinesis-ergo.com/split-keyboards/
- http://xahlee.info/kbd/keyboard_switch_mechanisms.html
- http://itravel.life/elecom-projection-bluetooth-laser-keyboard-review-cellluon/