Convert String Catalog to ARB online
Upload a Xcode String Catalog (.xcstrings) file and download it as Flutter ARB. Translation keys, plurals and placeholders are preserved. Free, no account needed.
Pick the source format or let the converter detect it from the file.
Choose the format you want to download.
Application Resource Bundle files are JSON documents with ICU message syntax and optional @metadata entries. Flutter's gen_l10n tool turns them into typed Dart localization classes.
Need it the other way round? Convert ARB to String Catalog.
From: Xcode String Catalog (.xcstrings)
String Catalogs were introduced in Xcode 15 and store all languages, plural variants and device variations of a project in one JSON-based .xcstrings file.
Used by: Xcode 15+, SwiftUI, iOS 17+. All languages in one file. Read the String Catalog format guide.
{
"sourceLanguage" : "en",
"strings" : {
"hello world" : {
"comment" : "My Hello World description",
"extractionState" : "manual",
"localizations" : {
"pl" : {
"stringUnit" : {
"state" : "translated",
"value" : "Witaj Świecie!"
}
}
}
}
},
"version" : "1.0"
}To: Flutter ARB
Application Resource Bundle files are JSON documents with ICU message syntax and optional @metadata entries. Flutter's gen_l10n tool turns them into typed Dart localization classes.
Used by: Flutter, Dart intl, gen_l10n. One language per file. Read the ARB format guide.
{
"@@locale": "en",
"hello.world": "Hello World!",
"@hello.world": {
"description": "Hello world message"
}
"my_address": "Address",
}How to convert String Catalog to ARB
- Drop your .xcstrings file into the converter above, or paste its content.
- Click Convert. You get one .arb file per language.
- Preview the result, copy it or download the files.
What changes between String Catalog and ARB
- String Catalog holds every language in one file, so the converter writes one ARB file per language found in the source.
Convert and translate in one place
If you need the ARB file in more languages, the fastest route is a free SimpleLocalize project: import the String Catalog file, add languages, run auto-translation with DeepL, Google Translate, OpenAI, Claude or Gemini, and download the result as ARB. The CLI does the same from CI with upload and download commands, so the conversion becomes part of your build. See also translating String Catalog files.
Frequently asked questions
Is the converter free?
Yes. There is no signup and no limit on the number of conversions beyond a few requests per second.
Are my files stored?
No. The file is parsed in memory, converted and returned in the same request. Nothing is written to disk or a database.
What about plurals and placeholders?
Plural forms are normalized to ICU message syntax and written back in the native form of ARB. Placeholders are kept, and Apple and Android specific syntax is translated between platforms. Read more in the pluralization guide.
Convert String Catalog to other formats
Convert other formats to ARB
Translate your ARB files
- Import String Catalog or ARB files into a free project
- Auto-translate with DeepL, Google, OpenAI, Claude or Gemini
- Download in any of the supported formats or publish to the CDN