Windows)¶

Purchase: Rainy75 (Amazon)

TL;DR

Switch between Kana and Eisu explicitly with a single key press — achievable via Rainy75 macros
Method A (VIA macro): No extra software. Send KC_LANG1/LANG2 on macOS for the quickest setup
Method B (OS tool): Use Karabiner / AutoHotkey v2 for reliable switching on any environment
VIA JSON files are available from the WOBKEY support page
On Windows, use AutoHotkey v2 (v1 is legacy)

You want to toggle Japanese IME with a single key press. You bought a Rainy75, but one-touch Kana/Eisu switching is not available out of the box. Online resources are scarce, and many users struggle with the setup.

This guide covers two field-tested methods to configure one-touch Kana/Eisu toggling on the Rainy75.

The Rainy75 is a 75% layout mechanical keyboard by WOBKEY (Keeb Inc.). It features a CNC 6063 aluminum case with gasket mount and comes in three variants: Lite, Standard, and Pro. It supports VIA, so key assignments can be freely customized via macros.

Only VIA is officially provided

The Rainy75 has official VIA firmware and JSON files, but no VIAL firmware or definition files are provided by the manufacturer. This guide uses VIA exclusively.

Method A: Send keycodes directly via VIA macros¶

Complete the toggle on the keyboard alone — no additional OS software needed. On macOS, registering KC_LANG1 (Kana) / KC_LANG2 (Eisu) in a macro is the simplest approach.

OS	Keycode	Notes
macOS	`KC_LANG2` (Eisu) / `KC_LANG1` (Kana)	Verified with JIS layout setting
Windows	IME toggle keys vary by environment	Method B recommended

Setup steps (example: CapsLock toggle)¶

Assign Macro1 to CapsLock in VIA
Set Macro1 to send LANG1 or LANG2
If it doesn't respond, check the keyboard type (JIS/US) setting on the OS side

In VIA's UI, KC_LANG1 / KC_LANG2 may appear as KC_HAEN (Han/Yeong) / KC_HANJ (Hanja). The names differ but the function is the same. If these have no effect, also try KC_EISU / KC_KANA.

VIA V3 now lets you insert delays directly from the macro editor. If keystrokes are too fast to register reliably, add a 20–50ms delay.

Loading the VIA JSON profile¶

To configure macros in VIA, you must first import a layout definition JSON. Download the Rainy75 JSON from the WOBKEY support page.

The JSON files are split by connection type and RGB support:

Connection	RGB	Non-RGB
Wired (USB)	Wired RGB	Wired Non-RGB
2.4GHz wireless	2.4G RGB	2.4G Non-RGB

Lite model note

The Lite has no RGB. Choose the "Non-RGB" JSON matching your connection type (Wired or 2.4G).

Import steps:

In VIA Settings, enable "Show Design tab"
Open the Design tab and Import the JSON
If the layout appears, you can now define macros in the Macro tab

The JSON's VID/PID must match your device. If the Rainy75 JSON uses the V2 format, select "Use V2 definitions (deprecated)" in the Design tab.

Method A is straightforward, but Windows IME behavior varies across environments. For reliable switching, consider Method B.

Method B: Toggle reliably via OS tools¶

Send a unique shortcut from the keyboard, then translate it to Kana/Eisu on the OS side. This approach absorbs IME differences and works consistently across setups.

The architecture is: Keyboard → unique shortcut → OS tool translates to IME switch.

macOS: Karabiner-Elements¶

Send RightAlt+K (Eisu) / RightAlt+J (Kana) from Rainy75 macros, and use Karabiner-Elements to convert them to the actual input method switch.

Register RightAlt+K and RightAlt+J in Rainy75 macros
Add Karabiner-Elements rules:
- RightAlt+K → Eisu
- RightAlt+J → Kana

RightAlt+K/J is rarely used in normal operation, minimizing accidental triggers. Reassigning CapsLock as a dead key makes the workflow even smoother.

Windows: AutoHotkey v2¶

Use AutoHotkey v2

AutoHotkey v1 is legacy — no new features are being added. Always use v2 for new installations. Download from the official site.

Send RightAlt+K/J from Rainy75 macros and control IME state directly via an AutoHotkey v2 script.

#Requires AutoHotkey v2.0

ImeSet(open) {
    hwnd := WinExist("A")
    imeWnd := DllCall("imm32\ImmGetDefaultIMEWnd", "ptr", hwnd, "ptr")
    PostMessage(0x283, 0x006, open ? 1 : 0, , "ahk_id " imeWnd)
}

RAlt & k::ImeSet(false)  ; IME OFF (Eisu equivalent)
RAlt & j::ImeSet(true)   ; IME ON (Kana equivalent)

This uses WM_IME_CONTROL to set the IME state directly, avoiding reliance on OEM-specific virtual key codes like {VKF0} / {VKF2} which vary by environment.

Some applications (e.g. UWP apps) may not respond to ImmGetDefaultIMEWnd. In that case, configure IME ON/OFF shortcuts in the OS IME settings and send those shortcuts from the Rainy75 macros instead.

Troubleshooting¶

If either method isn't working, check the following:

Symptom	Cause & Fix
No effect	JIS/US layout mismatch between OS and VIA. Verify OS-side settings
Requires double press	Add a delay (20–50ms) to the macro. VIA V3 supports this directly in the UI
LANG½ ignored on macOS	Switch to Method B (Karabiner-Elements)
VIA doesn't recognize the keyboard	See checklist below

VIA recognition checklist:

Confirm firmware supports VIA (get the latest from the WOBKEY support page)
Import the correct JSON (matching VID/PID) in the Design tab
Try a different port/cable with a direct connection (avoid USB hubs)
Try Chrome-based VIA at usevia.app
On macOS, allow the input device access prompt. On Windows, switching to WinUSB via Zadig may help in some cases, but overwriting the HID driver can break other input — use this as a last resort only

Which method should you choose?¶

The right choice depends on your OS and how much setup you're willing to do.

Factor	Method A (VIA macro)	Method B (OS tool)
Extra software	None	Karabiner / AutoHotkey required
macOS stability	Good (with JIS setting)	Excellent
Windows stability	Inconsistent	Good (AHK absorbs differences)
Best for	macOS + JIS, quick setup	Windows, or cross-environment reliability

VIA updates or firmware changes may alter these steps in the future. Check the WOBKEY support page for the latest information.