How to Fix the Annoying Mac Yen (¥) Key to Type a Backslash (\) in Google Chrome

If you use a physical Japanese (JIS) hardware keyboard layout on a modern Mac, you have likely run into a frustrating quirk: even if you change your macOS text settings to output a backslash (\) instead of a Yen sign (¥), Google Chrome, VS Code, and Slack will completely ignore your system settings.

While the macOS Terminal respects the software substitution, web browsers and electron apps read the raw hardware keycode (0x5C) directly from your Japanese keyboard, forcing the ¥ symbol onto your screen unless you hold down Option + ¥.

After battling with read-only folder permissions and silent file deletions on modern macOS, here is the definitive guide to fixing this at the layout level without installing heavy background remapping software.

The Core Issue: Why System Settings Fail

When you change the setting under System Settings > Keyboard > Input Sources > “¥” key generates, macOS only applies this change as a text-substitution layer.

Applications like Google Chrome bypass this layer. They look straight at your hardware layout configuration file. Because modern macOS locks down system folders with System Integrity Protection (SIP), trying to manually drop custom keyboard layout files into /Library/Keyboard Layouts/ will result in macOS silently deleting the file to protect system integrity.

The Solution: A Custom User-Level Layout Bundle

To fix this permanently, we will create a modified keyboard layout using a free utility, and install it to the isolated User Library directory where macOS security policies allow it to run.

Step 1: Create the Modified Layout in Ukelele

  1. Download and install the free keyboard layout editor, Ukelele.
  2. Open Ukelele and go to File > New Based on Current Input Source.
  3. By default, Ukelele might show a standard US ANSI grid layout, making your hardware Yen key invisible. To fix this, go to the top Mac menu bar and select View > Keyboard Type > JIS (Japanese).
  4. The on-screen keyboard will refresh to match your hardware layout. Locate the ¥ key (usually next to the Backspace/Delete key).
  5. Double-click the ¥ key inside the visual editor, type \ (Backslash) into the field to replace it, and save the project as a Keyboard Layout Bundle (e.g., ABC-JIS.bundle).

Step 2: Install the Layout Without Trimming File Permissions

Do not try to drag and drop the file manually into the root system folder, or macOS will instantly erase it. Instead, use the built-in macOS installer pipeline:

  1. Double-click your saved .bundle file from your desktop or downloads folder.
  2. A macOS system dialog box will pop up asking if you want to install it.
  3. Click Install for current user.
  4. macOS will automatically securely copy the bundle into your hidden user directory: ~/Library/Keyboard Layouts/.

Step 3: (Optional) Give Your Layout a Clean Name

By default, macOS might label your newly created input source as something generic like “ABC copy.” To customize this:

  1. Go to Finder, click Go in the top menu bar, hold down the Option (⌥) key, and click the hidden Library folder that appears.
  2. Navigate to Keyboard Layouts, right-click your .bundle file, and select Show Package Contents.
  3. Open Contents > Resources > en.lproj (or your primary language folder).
  4. Open the InfoPlist.strings file with TextEdit.
  5. Locate the string value showing "ABC copy" and change it to your preferred name (e.g., "ABC-JIS+backslash").
  6. Save and exit.

Step 4: Activate and Reboot

  1. Click the Apple Logo > Restart… to clear the macOS input method cache. A simple logout is not enough!
  2. Once rebooted, open System Settings > Keyboard.
  3. In the Text Input section, click Edit… next to Input Sources.
  4. Click the + (Plus) button at the bottom left, scroll down to Others, select your custom layout name, and click Add.
  5. Remove your old default layout by selecting it and clicking the - (Minus) button so your system doesn’t toggle back to it by accident.

The Verdict

Your Mac will now default to your custom hardware map. Because this fix sits right inside your user-level input sources, Google Chrome, VS Code, and every other stubborn application are forced to read the physical key press as a native backslash. No background apps, no performance lag, and no more holding down the Option key while programming!