8BitDo Retro 108 on a Mac: Key Setup, Fn and Touch ID

8BitDo Retro 108 mechanical keyboard

The 8BitDo Retro 108 is a fun keyboard to look at and a precise one to type on. It’s also built for Windows. 8BitDo lists Windows and Android as the supported systems, so on a Mac three things go wrong straight away: Command and Option sit in the wrong places, the Fn key does nothing macOS can see, and you lose Touch ID the moment you close the laptop lid.

All three are fixable in a few minutes. Here’s the setup I use with my Studio Display and MacBook Pro, followed by the keyboards I’d look at if you want the same precision without the noise.

Put Command Next to the Space Bar

The key next to the space bar on a Windows layout is Alt, which macOS reads as Option. The Windows key, one further out, becomes Command. Your thumb expects the opposite, so the two need swapping.

Do the swap in one place only. The Retro 108 can swap keys in its own firmware with 8BitDo’s Fast Key Swap (Win, Alt and the ★ button above the F keys), and a second swap on the Mac cancels it out. Clear the keyboard’s swaps first by holding ★ for five seconds, as 8BitDo’s manual describes, and do the swap on the Mac with Karabiner-Elements, set up below.

The keycaps still say Win and Alt. It’s a mechanical board, so you can pull the two caps and swap them too.

Get a Real Fn Key for Dictation and Globe Shortcuts

The Retro 108 has an Fn function, but it lives inside the keyboard: it changes what other keys send and sends nothing itself. Apple’s Fn, the Globe key, uses its own signal outside the standard keyboard codes, and almost no third-party keyboard sends it.

So Fn+E won’t open the emoji picker, Fn+Ctrl+arrows won’t tile windows, and dictation apps that default to holding Fn won’t hear you. Wispr Flow’s documentation plans for this: if it doesn’t detect an Apple Fn key during setup, it moves push-to-talk to Ctrl+Option.

The fix is to turn one key into Apple’s Fn on the Mac side. Right Control is the least-used key on the board and sits under your right hand, which makes it a good dictation key. Once it’s remapped, holding it works exactly like holding Fn on a MacBook, and Wispr Flow works with its default Fn shortcut.

Set Up the Retro 108 With Karabiner-Elements

Karabiner-Elements is a free, open-source remapper that changes keys at the driver level, before macOS sees them. Rules can be limited to one keyboard, so your MacBook’s own keyboard stays as it is, and they apply the moment the keyboard connects, including straight after a restart.

Install it, then approve what macOS asks for under System Settings, then General, then Login Items & Extensions: Karabiner’s background items, and its driver under Driver Extensions. If the driver switch won’t turn on and Karabiner keeps showing “waiting for user”, run its activation command in Terminal:

/Applications/.Karabiner-VirtualHIDDevice-Manager.app/Contents/MacOS/Karabiner-VirtualHIDDevice-Manager activate

Then open Karabiner’s Devices tab and turn on Modify events for the 8BitDo Retro 108.

The remaps go in karabiner.json in ~/.config/karabiner, in a device entry for the Retro 108 (vendor ID 11720, product ID 21001). These are the ones I use:

Left and right Alt to Command, and left and right Win to Option.
Right Control to Apple’s Fn.
Scroll Lock and Pause to brightness down and up.
Print Screen to CleanShot X‘s area capture.

The Fn rule looks like this:

{ "from": { "key_code": "right_control" },
  "to": [{ "apple_vendor_top_case_key_code": "keyboard_fn" }] }

Brightness uses display_brightness_decrement and display_brightness_increment as consumer key codes. Print Screen needs a complex modification, because it runs a command instead of sending a key: it runs open -g 'cleanshot://capture-area' through CleanShot’s URL scheme, so Cmd+Shift+4 keeps working on the laptop keyboard.

Karabiner may list the Retro 108 twice, once as a keyboard and once as a keyboard plus pointing device. Put your remaps on both entries, so it doesn’t matter which one it uses.

Replace Touch ID When the Lid Is Closed

Apple only lets its own sensors do Touch ID. Each sensor is paired with the Mac’s Secure Enclave, and macOS ignores third-party fingerprint readers. Apple’s Magic Keyboard with Touch ID is the only keyboard that has it, and there’s no Face ID on the Mac either.

That hurts if you approve a lot of things during the day. I use 1Password for everything, and its command-line tool asks for approval every time a new terminal session needs a secret. With AI agents like Claude Code opening sessions all day, that’s a lot of approvals.

There are three ways around it, and one way to need them less.

Apple Watch is the official replacement. With “Use Apple Watch to unlock applications and your Mac” turned on under Touch ID & Password, and the Apple Watch option switched on in 1Password’s Security settings, prompts go to your wrist and you approve with a double-press of the side button. It needs the Mac signed in to iCloud with the same Apple Account as the iPhone the Watch is paired with, and you have to be wearing the Watch.

Keeping the laptop open works too. Leave the MacBook beside the keyboard and the sensor stays in reach. The cost is a second screen your Mac is driving. BetterDisplay can disconnect the built-in display while the lid stays open, but that’s a Pro feature at $21.99 (€19.99) one-time, with a 14-day trial. Turning the brightness to zero is the free fallback, though macOS still renders to that screen.

A Magic Keyboard with Touch ID next to your main keyboard gives you a fingerprint pad with the lid closed. It’s the only way to get the sensor itself, and it’s a whole keyboard used for one key.

Fewer prompts make all of the above easier. Credentials that scripts read on every run, and that don’t carry much risk, can live in the macOS Keychain instead of 1Password. Each tool then reads them without asking, and the prompts that remain are the ones worth stopping for.

Start with the Keychain cleanup, then pick the Watch if you wear one. With the routine prompts gone, a double-press now and then is easy to live with.

Make the Retro 108 Quieter

The Retro 108 ships with Kailh Box White V2 switches, which are clicky on purpose: a small metal bar inside each switch snaps to make the sound. That click is separate from the bump you feel when a key registers, and the bump is where the sense of accuracy comes from.

The board is hot-swappable, so you can pull the switches and push in quieter ones without soldering. Silent tactile switches keep the bump and lose the click. The Gazzew Boba U4 is the best-known one and feels soft and cushioned at the bottom of each press. Order the U4, not the U4T, which is the loud version. Check whether your board takes 3-pin or 5-pin switches first; you can clip the two extra plastic legs off 5-pin switches to fit a 3-pin socket.

O-rings and a desk mat help a little with bottom-out noise. Neither does anything about the click.

Quieter Top-Tier Keyboards for the Mac

There’s no Aeron of keyboards that everyone agrees on, but a few names lead most recommendations for people who want something quiet, comfortable and built to last. None of them has Touch ID. If a keyboard’s Fn key doesn’t reach macOS, the Globe remap above works on any of them.

The Realforce R3 is the one to look at if you want a normal full-size layout. It uses Topre switches, made by Topre itself: a rubber dome over a spring, sensed electrically, so there are no contacts to wear out. The feel is soft and rounded with a muted thock, and there’s a Mac version with Mac legends.

The HHKB Professional HYBRID Type-S has the same Topre feel in a compact layout that keeps your hands on the home row. Control sits where Caps Lock usually is, and arrows and function keys sit on a layer. It has a devoted following among programmers. Type-S is the silenced version.

The Keychron Q Max series, the Q1 Max or the full-size Q6 Max, gives you a heavy aluminum case, a gasket mount that cushions every press, Mac keycaps in the box and open firmware you can remap on the keyboard itself. It’s hot-swappable, so you can choose how quiet it is by picking the switches.

The Logitech MX Mechanical for Mac is the easy route: low-profile, Mac legends, three-device switching and a quiet tactile option. It’s less special to type on than the other three, and it doesn’t need a wrist rest.

If I had to pick one without trying them, I’d go for the Realforce R3 Mac. It’s the closest to quiet, comfortable and top-tier without asking you to learn a new layout. If you like the 8BitDo’s feel and just hate the noise, a set of silent switches costs far less and gets you most of the way.