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CLI

File formats

The translation file formats the CLI can read and write.

1 min read ยท Updated October 2026

Set format in ct.yml to the format your code loads. ct init --format po --source-language de writes it for you.

formatFiles
jsonJSON
yamlYAML
xliffXLIFF
poGettext
androidAndroid strings.xml
stringsiOS .strings
propertiesJava properties
arbFlutter ARB

How files are mapped #

  • Every language lives in its own file, named by translations ({lang} is the language code).
  • Spreadsheet-style formats with several languages per file (CSV, Excel, Apple String Catalog) can be imported and exported in the web app instead.
  • XLIFF and Gettext files carry the source text next to the translation. The source file is read for its source texts, and pulled files contain them as well.
  • Gettext uses the msgctxt as the key when there is one, otherwise the msgid.

Messages #

Messages are passed through untouched, so ICU syntax such as {count, plural, ...} round-trips.

  • Gettext, Android and YAML plurals are converted to ICU plurals when they are pushed. When pulling, ICU messages are written as plain messages.
  • Nested JSON becomes dotted keys (checkout.title) and is nested again on pull.
  • Values that are not text are skipped with a warning.