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Ergohaven K:03 review

I tested Ergohaven's K:03, a 60% true split, the latest member in the ever growing family of keyboard models offered by the team.
Published May 31, 2024
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The K:03, a reiteration of the K:02 by Ergohaven, is a prebuilt split keyboard in a new 3D printed case. After all their recent models with keywell (Velvet, Remnant, High Plains Drifter), the Ergohaven K:03 is a good-old split with flat plates.

TLDR; The K:03 by Ergohaven is a Vial-compatible prebuilt split keyboard with full number row, ready to rock right out of the box. It's affordable, hotswap, has a 3D printed case, tenting feet, and beside OLED displays it comes with optional encoders.

The names K:01 and K:02 indicated the first and second prebuilt keyboards offered by Ergohaven, but after many more boards designed since those early days, K:03 simply means the third model in this specific lineage: the true flat splits with about 60% form factor.


Two things before we start with this review:

  • Ergohaven offered me this keyboard for free (thanks!). As usual, this may result in all kinds of bias, both positive and negative in my experience, so read everything I write with a grain of salt.
  • Secondly, Ergohaven is based out of Russia. Before hitting the Buy button, consider if that's in accordance with your worldview. (For context, here is an interview with Evgeny.)

Unboxing and Content

The small box the K:03 comes in is barely larger than the footprint of a single keyboard half (17x15x7cm), and it's perfect for transport. The design has changed a bit: while previous boards came in a white cardboard box, this one has the distinctive recycled look.


The box conceals the split keyboard itself with keyswitches and caps mounted, two cables, 15mm tenting legs (Universal Tenting System), and a black velvety pouch.


Still no keycap/switch puller, which is totally fine if you already sit on a heap of these tools like I do. However, it would come in handy for somebody new to the mechanical keyboard hobby.

Unlike earlier Ergohaven models, there is an USB-C to USB-C cable between the halves, not a flat TRRS cable with the L-shaped connector. As a result, you can't really pack up your rig without disconnecting the halves anymore, as you could do with the K:02.

Ergohaven K:03 features

  • prebuilt split
  • 58-60 keys (4x6+5)
  • MX, hotswap
  • RP2040-Zero controller
  • encoder (optional)
  • indicator LED
  • USB-C cables
  • 3D printed case
  • carry pouch


Like with previous boards in this series, you get a pretty common split layout with slight columnar stagger. It's a decent, proven keyboard design, nothing revolutionary or experimental – except maybe the new shape of the case and the new layer indicator LED, which is not common.


The blank white caps match the clean and simple design perfectly.

Actually, it seems like the K:03 is a true split version of the Planeta or an improved K:02 with optional encoders and many more tweaks. With regards to the design language, especially case design, it closely follows the Imperial44, the numrowless little brother.

Build quality

I'm still not into 3D printing so can't really judge the quality of the print. It looks fine for my untrained eyes. The white PLA is more classy than the black color of the original K:02. As already mentioned in the Velvet 2 review, I like the white versions much better: Layers of the 3D printing are less obvious, and they simply look better imo. No wonder that the official photos on the Ergohaven site are overwhelmingly about the white ones, this colorway works very well in photos.

The minor imperfections I discovered in concave corners of previous models are mostly gone now. That said, don't expect the quality and tolerances of a CNC'd alu case.


The case, despite being 3D printed, is not too light at all, you won't toss it around on your desk accidentally. The new case design makes the K:03 sit very stable.


The cut-out for the small OLED displays is better than before. In addition, there are indicator LEDs on both sides now.

Physical layout, form factor

Basically 6x4 halves – full number row –, plus 5 "thumb keys". As usual, three thumb keys + 2 keys in the bottom row I'd say, since I personally wouldn't use the two inner ones as thumb keys. They are probably meant to be hit with your middle and ring fingers.

58 or 60 keys – depending on if you'd like the board built with or without encoders. Much more keys than I'm used to, but as always: more keys can't hurt… much. :) To play it safe, I don't assign any functions to the extra two keys of the "thumb cluster" to avoid accidental keypresses.


The K:03 comes with a conservative columnar staggering: about 0.5U for the pinkies.


Ergohaven offers the K:03 with uniform white DSA or XDA caps (but also as barebone, without any caps). As you can see in the photos, I got the DSAs for variety.


Blank uniform caps are an obvious choice for touch typers. Even if I'm not too enthusiastic about uniform XDA/DSA on a flat plate and especially in the thumb cluster positions, I've been using my Planeta with the stock XDA caps for months, so they definitely work.

Because of the 58-60 all-1U layout, it may prove challenging to populate the board with smaller sculpted sets. The low pro (MX) cylindrical caps by Tai-Hao worked like a charm for the thumb part:



The K:03 is hotswappable, so if you are into switches, you can get the board as a barebone kit. For others, switch models on offer are Gateron Brown G Pro 3, and Ruby/Purple Panda/Pudding Medium from Tecsee. I got the 50g tactile Mediums: a "new wave" low-pro switch by Tecsee with MX stems and only 2.5mm travel.


However, since the K:03 is hotswappable, you can use your favorite switches and replace them as you wish.


For the switch replacement, I prefer to disassemble the board to be able to support the hotswap sockets, preventing lifting the traces. The single-part housing with the switch plate snapped in without any screws makes relatively easy. (Use the holes for the optional tenting legs to gently push the PCB/plate out.)


Speaking of disassembly, here you go:


As you can see, the board uses a surface soldered RP2040-Zero. The soldering job is much cleaner than last time. Haven't experienced any problems.



As you may be already familiar with this from all the recent Ergohaven write-ups, the K:03 is compatible with their in-house "universal tenting system" – 3D printed legs with bumpons in various sizes. (In contrast to the fixed-angle 15° magnetic tenting feet of the original K:02.)


The K:03 is accompanied by four 15mm legs – two for both halves. Other sizes are available in their online store.


No per-key LEDs. Bad news if you are into them, no problem for me personally. I always have to remind myself to put back the RGB functions for the sake of reviews/photos after, as the very first step, I've overwritten them in Vial with more useful stuff.


That said, there are now two indicator LEDs, one on each half, which provide feedback about the active layer – colors matched to that of the red/blue accents of the keycaps.

OLED displays

You can plug your cable in either half which decides their master/slave relations and also the functions of the displays.

By default, the OLED of the master half shows useful info about the firmware version, mode (Win in the photos), active layer, and Caps Lock status.


On the slave half there's a cool animation with the ergohaven logo.


In addition, Ergohaven implemented new screen modes for the K:03 and other models (haven't tested it yet but will get back to this), which is done in Vial but requires updating the firmware.

Modes: 1. Classic Status, 2. New status, 3. Minimalistic status, 4. Screensaver (different for each model), 5. Bongo Cat, 6. Turn off screen.

Both screens turn off automatically after one minute of inactivity.

Firmware, software

The K:03 is Vial compatible. It works right out of the box, at least if you type in English, which is always a nice experience after all the handwired boards and kits. No need to solder and flash anything. ;)

Thanks to its Vial compatibility, adapting the layout to your needs is pretty easy and self-explanatory.


As always, reproducing my pretty elaborated layout took some time, but that has nothing to do with this particular keyboard, rather than the fact I type in various languages which are hardly compatible with each other. Not to mention the symbol layer when changing languages.


I've been using the K:03 for about a week now, without any problems. It was exposed to some heavy office work: coding, writing emails, including typing this very article.

As someone who is accustomed to splits, the K:03 required minimal adaptation after the initial setting up period. If you're new to split life, however, expect a longer learning curve to get used to the layout and keymap. That said, the K:03 with its fairly conservative stagger and relatively many keys (at least when it comes to splits in general) may be a great first board given it's offered as a prebuilt or barebone.

Where to buy the K:03?

It's available starting at $150 at ergohaven, international shipping is arranged from Kazakhstan:

(The Takoland deskmat in the photos came from Zion Studios.)


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Published on Fri 31st May 2024. Featured in KBD #166.


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