Why Use A Split Keyboard? 7 Evidence-Backed Benefits

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• Split keyboards straighten your wrists and forearms, cutting ulnar deviation by up to 25°
• Users report less shoulder tension and forearm pronation within a week
• Long-term studies link split layouts to lower muscular/skeletal discomfort scores 
• Compact 40% - 60% split boards free up desk space and improve mouse reach and usability
• No measurable drop in typing speed after adaptation, and even a gain in typing speed is not unusual
• The ergonomic keyboard scene continues to grow, signaling proven benefits and a healthy ecosystem

What Is A Split Keyboard?

A split keyboard divides the keys into two independent halves, allowing you to set each half shoulder-width apart (or wherever you want) and tent the halves for a neutral wrist angle. The goal is to keep wrists straight (no inward bend) and let forearms rest in a natural posture.

The 7 Core Benefits

Neutral Wrist & Forearm Posture

Standard one-piece keyboards force your wrists into ulnar deviation and pronation. Tests performed on experienced typists showed that an adjustable split layout reduced ulnar deviation by ~25 % and wrist extension by ~6 ° without impacting WPM. Over long shifts, that deviation difference adds up, easing tendon stress and keeping the carpal tunnel open.

Relaxed Shoulders and Upper Back

When you place each half of a split keyboard shoulder width apart, your elbows stay closer to 90 °, resulting in less internal shoulder rotation. Participants in a 2023 workplace trial reported a noticeable drop in shoulder and upper back fatigue after switching to fully split or “column-staggered” boards. Even though shoulder-width is the most common, you can place the halves at any position that works best for your body and keeps your posture in a healthy and natural position.

Lower Risk of RSI and Carpal Tunnel

A five-month follow-up study tracked office workers using a tented 12° split keyboard and found significant improvements in self-reported discomfort vs. a control group using standard keyboards. While no design can guarantee you will be permanently injury-proof, every major RSI guideline cites reducing wrist deviation as a key prevention method.

Personalized Comfort & Adjustability

Unlike single piece keyboards, split keyboards allow you to:

• Angle halves (tenting) to match arm pronation
• Separate halves to varying degrees to match your natural shoulder width
• Tilt or rotate each half independently to let you type without bending your wrist

Single piece keyboards are simply unable to offer these proven ergonomic benefits. Split keyboards account for anatomical differences which single piece keyboards ignore.

Compact Options

Ergonomics isn’t only about posture; it’s also about reach, arm movement, and finger movement. Compact 60% or especially 40% split keyboards bring the mouse closer to your midline, cutting lateral shoulder travel. These smaller columnar stagger options also greatly reduce finger movement while typing, which leads to reduced strain and fatigue.

Maintains or Improves Typing Speed

A field survey of 200 typists found no statistically significant reduction in throughput after a two week learning curve on split keyboards. Some users gained WPM thanks to better finger alignment, reduced reach, and improved comfort.

A Future Proof and Upgradeable Tool

The ergonomic keyboard scene is consistently growing and is projected to triple in the next 10 years. More people who use a computer daily and type frequently are learning about the benefits and prioritizing their health. This means a growing ecosystem of mods, continued product support, and a growing community.

Split Keyboard vs. Regular Keyboard

How to Choose the Best Split Keyboard

Layout Size

Common split keyboard sizes are 60% and 40%, with 30% also being in the mix but less common. Smaller layouts reduce movement and desk clutter, which is great for portability and keeping your setup sleep and compact. 60% boards retain the number row for easier typing but are a bit larger in size. If you aren't sure where to start, we highly recommend a split 60% keyboard, like the Lily Pad. The smaller the layout, the larger the learning curve and adjustment period. 60% split keyboards are generally very easy to adjust to.

PCB Assembly Type

There are two version of PCBs: SMT PCBs and DIY solderable PCBs. If you are looking for a plug-and-play option choose an SMT PCB, these are soldered by the manufacturer and come ready to go out of the box (no soldering required). DIY solderable PCBs are also available but require soldering by the user. There are some pros and cons to each, but most of the time an SMT PCB is the easy friction-free option.

Firmware - QMK or ZMK?

The short answer is QMK and VIA for wired USB-C split keyboards, and ZMK is for wireless split keyboards. Both firmwares offer full programmability and customization. Firmware depends on the PCB you purchase or the controller you're using for your build. All of our SMT PCBs are pre-flashed with QMK/VIA maps, and all of our boards have ZMK keymaps available if you're doing a wireless BLE build.

Case Material

Aluminum cases feel premium, are extremely durable, and sound great. As a result, aluminum cases are considered the 'top of the line' option. The downside of aluminum cases is the premium cost they carry. Compared to other materials, aluminum is also heavy. FR4, acrylic, or 3D printed cases offer different benefits and are usually readily available for popular layouts. These different materials are all offered at various price points and have unique benefits, features, and acoustic profiles. Overall, aluminum cases like the Unicorne are seen as the best or highest end option, and cases like FR4 cases are seen as the best value option and can be a great way to try a layout or see if you like a split keyboard.

Tenting and Stands

Tenting is one of the largest ergonomic upgrades you can make in your setup. Studies show tenting greatly reduces wrist strain and really is the 'final piece of the puzzle' in terms of ergonomics. At Boardsource, we have designed our own tenting system that is interchangeable across all of our products, the Boardsource Booster Packs. Ensure your split keyboard is compatible some tenting system so you can tent your board if you want to! Even if you don't do it right at the start, it's a nice option to have later.

Connector Style

TRRS Connection, USB-C, or true wireless? In terms of wired keyboards, USB-C connectors have become the standard for both connection to your computer and connection between the two halves thanks to their improved durability and damage-free hot plugging. It is highly recommended to purchase a board with USB-C connections if you're able to, but some designs still use TRRS connectors which is okay. True wireless keyboards using BLE controllers and ZMK do not need any connection to your computer, and communication between halves is also wireless.

Keycap & Switch Compatibility 

Some boards use MX style switches, others use Choc v1 or v2 low-profile switches. Make sure you understand which type of switch your board is compatible with. Sometimes PCBs are compatible with multiple types of switches (on a single board). There are pros and cons to both MX and LP switches, most of the ergonomic benefits of a split keyboard are switch-independent, meaning if you go MX or LP it's mostly personal preference has no impact on the ergonomics. Usually PCBs include hotswap sockets, meaning, you can change out your switches without any soldering. These sockets are compatible with either MX or Choc switches. 

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