i18n JSON Validator - find missing translation keys | POLPROG
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i18n JSON Validator BETA

Validate your localization files and catch missing keys, inconsistencies and potential issues before release.

Free to use No registration Privacy-first
Files are validated on our servers and never stored or shared.
Supported structure
  • ✓
    Flat JSON{ "key": "value" }
  • ✓
    Nested JSON{ "key": { "nested": "value" } }
  • ✓
    Placeholders{name}, %s, {{value}}
  • ✓
    HTML tags<b>, <a>, <br> and more

Tip: Name your files with the language code (e.g. en.json, pl.json, de.json) for best results.

Files are validated on our servers. We do not store or share your data.
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