How to Localize Claude Code and Codex to Chinese: A Step-by-Step Guide

For developers in China who are new to Claude Code and Codex, an all-English command-line interface is often the very first barrier to getting started. While users with strong English skills can navigate it without issues, a Chinese interface can significantly reduce cognitive load and improve workflow efficiency for those who prefer it. Based on a hands-on demo by Bilibili creator "大海的科技宝箱", this guide walks through how to localize Claude Code and Codex to Chinese on both Mac and Windows.

Why Claude Code and Codex Don't Support Chinese Out of the Box

Many users discover an awkward reality after installing Claude Code or Codex: the interface is entirely in English, and there's no straightforward way to switch languages through the official settings.

The two tools handle this differently:

• Claude Code: The settings themselves are in English, and the native version offers no Chinese language option — no matter how thoroughly you dig through the settings, there's no language toggle.
• Codex: The settings do include a Chinese option, but even after selecting it, the interface still displays in English — a half-baked localization implementation.

This is precisely why relying on official settings won't solve the problem. The solution requires a third-party localization tool that replaces the interface text directly. That's the core approach this tutorial covers — using an external script to process the language resources embedded in the program.

Claude Code is Anthropic's AI-powered coding assistant for the command line. Built on the Claude model, it lets developers invoke AI directly from the terminal to handle tasks like code generation, refactoring, and debugging. Codex is OpenAI's equivalent tool (not to be confused with the earlier model of the same name), also centered on a command-line interface. In both tools, the underlying interface text is hard-coded into program resource files (typically JSON or JS language packs) rather than being dynamically read from the operating system's language settings — which is fundamentally why changing your OS language has no effect on how these tools display.

API relay is a common access method for users in China: since Anthropic and OpenAI's official services have access restrictions for mainland China IPs, some users connect through third-party relay service API endpoints instead of using official account subscriptions directly. These two access methods differ in how configuration file paths or authentication logic work inside the program, which is why the localization script needs to handle them differently — and why the localization options distinguish between "official subscription" and "API relay."

Step-by-Step: Localizing Claude Code

The localization tool is straightforward to use. The package includes two platform-specific script files — one for Mac and one for Windows — along with a usage guide. Simply double-click the script for your operating system to get started.

Understanding the Options: Official Subscription vs. API Relay

After double-clicking the script, the program enters an interactive prompt asking you to select your current access method. Choose based on how you're connected:

• Option 1 (Official Subscription): Select this if you're logged in with an official account (including free accounts). After the script finishes, simply restart the interface and it will display in Chinese.
• Option 2 (API Relay): Select this if you're connecting via an API relay service.
• Option 3: The creator explicitly states this option is not recommended for everyday use — options 1 or 2 will cover most scenarios.

The script will also ask whether you want to enable auto-updates, uninstall the language pack, or sync cc switch skill settings. For most users, these additional options can safely be ignored — they're not related to the core localization function.

How Long It Takes and Troubleshooting Common Issues

The localization process takes some time. In the demo, the progress bar ran through approximately 2,467 items, with the entire process taking about 4 minutes. Note that progress is slower at first and speeds up noticeably after the halfway point. Once it completes, press Enter to exit.

Here's a common pitfall worth calling out: if you selected Option 2 (API relay) but are still logged in with an official account, opening Claude Code after localization will show the interface still in English. This isn't a failure — it means the active access channel doesn't match your localization configuration.

The fix is to use the cc switch tool to switch from official to API access mode, then restart Claude Code. After restarting, the interface may show a "using gateway" notice — you can ignore this. The interface will now display fully in Chinese.

How to Localize Codex

The Codex localization package has a similar structure to Claude Code's — it contains two folders, one for Windows and one for Mac. Navigate to the folder for your system, refer to the included guide, and double-click the script to apply the localization.

Uninstalling is equally simple: just double-click the corresponding script again to remove the localization. The overall process closely mirrors Claude Code's — it's a double-click-and-done operation that requires no additional configuration.

Localization Results and Known Limitations

After completing the localization, Claude Code's language settings will include a new "Simplified Chinese" option, and the vast majority of the settings interface will display in Chinese.

To be transparent: localization coverage is not 100% — the creator noted that a small number of areas remain in English. However, these gaps don't affect normal use, and all the key areas you'll encounter in day-to-day operation have been translated.

For developers with limited English proficiency who want to get up and running quickly with these AI coding tools, this type of third-party localization is a practical interim solution. That said, keep expectations realistic: since the tool modifies the program's language resources, localization may break or need to be re-applied when Claude Code or Codex releases an official update — which is exactly why the script includes an "auto-update" option.

The way third-party localization tools typically work is by locating the language resource files in the program's installation directory, batch-replacing English strings with their Chinese translations, and writing the changes back to the original files. This approach is known as "resource file patching" — the advantages are that it doesn't modify program logic and is fully reversible (just run the uninstall script to restore the originals). The downside is tight coupling to specific software versions: once the developer releases an update that changes the resource file structure or adds new text entries, the existing patch breaks and needs to be re-applied after the localization tool author releases an update. The "auto-update" option is designed to address this — it lets the script detect version changes and automatically re-apply the localization, reducing manual maintenance. Users should keep an eye on the localization tool's changelog to verify compatibility with the latest version.

Summary: Key Things to Remember

Overall, this localization approach has an extremely low barrier to entry: download the package, double-click the script for your OS, select the option matching your account type, and wait a few minutes. The only critical point is this: the localization option must match your actual access method (official subscription or API relay). A mismatch is the most common reason the interface stays in English even after localization completes.

Community-driven localization efforts like this are commendable for making AI coding tools more accessible in China. In the long run, however, proper interface localization ultimately needs to come from the official developers to ensure update stability and complete coverage.