Features

• Works with JSON-based i18n setup
• No installation required — npx i18n-gap
• Detects missing translations across all languages
• Detects orphaned keys that don't exist in reference language
• Easy editing of missing translations via JSON

Usage

By default, i18n-gap will use en as the reference language and compare all other languages against it.

$ i18n-gap generate

Reference language: en
Analyzing 3 languages: en, fr, es

en: reference (42 keys)
fr: 6 missing
  app.title
  user.greeting
  ... +4 more
es: 12 missing

Generated: translation-gaps.json

This creates a translation-gaps.json file with all missing keys:

{
  "fr": {
    "app.title": "My App",
    "user.greeting": "Hello, {{name}}!"
  },
  "es": {
    "app.title": "My App"
  }
}

Fill in the translations:

{
  "fr": {
    "app.title": "Mon Application",
    "user.greeting": "Bonjour, {{name}} !"
  },
  "es": {
    "app.title": "Mi Aplicación"
  }
}

# Preview changes
$ i18n-gap apply --dry-run

fr: would add 6 translations
  + app.title: Mon Application
  + user.greeting: Bonjour, {{name}} !
  ...

# Apply when ready
$ i18n-gap apply

fr: +6
es: +12

Added 18 translations

$ i18n-gap stats

en     ██████████████████████████████ 100.0% 42/42 (reference)
fr     ████████████████████░░░░░░░░░░ 85.7% 36/42 (6 missing)
es     ███████████████░░░░░░░░░░░░░░░ 71.4% 30/42 (12 missing)

1/3 complete, 2 need attention

Config

See i18n-gap help for more details.

Config File

Create .i18ngaprc.json in your project root — npx i18n-gap init

{
  "i18nDir": "./src/assets/i18n",
  "outputDir": "./",
  "referenceLang": "en",
  "ignoreLangs": []
}

CLI Options

Override config with flags:

i18n-gap generate --dir ./locales --ref fr
i18n-gap generate --ignore dev,test
i18n-gap apply --dry-run

Commands

i18n-gap generate      # Find missing translations
i18n-gap stats         # Show completion statistics
i18n-gap apply         # Merge completed translations
i18n-gap init          # Create config file

License

MIT License © 2025 rznn7