---
title: addLanguage
description: Add a new target language to a project.
---

Add a new target language to the project. Use ISO 639-1 language codes.

## Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| `project` | string | Yes | Project identifier in `org/project` format |
| `languageCode` | string | Yes | ISO 639-1 language code (e.g., 'fr', 'ja', 'de') |

## Example

```json
{
  "project": "my-org/my-app",
  "languageCode": "ja"
}
```

## Response

```json
{
  "success": true,
  "message": "Language 'ja' added successfully",
  "languageCode": "ja",
  "project": "my-org/my-app",
  "alreadyExists": false
}
```

## Common Language Codes

| Code | Language |
|------|----------|
| `en` | English |
| `tr` | Turkish |
| `de` | German |
| `fr` | French |
| `es` | Spanish |
| `ja` | Japanese |
| `ko` | Korean |
| `zh` | Chinese |
| `ar` | Arabic |
| `pt` | Portuguese |

## Notes

- If the language already exists, `alreadyExists` will be `true`
- Adding a language creates empty translations for all existing keys
- Use AI translation to populate the new language quickly
