Problem

Indesign has a language setting. This typically points to the source language of a translationi job.

Other translation tools are capable of changing it to the target language.

Solution

There needs to be a mapping between translate5 languages and Indesign languages in the IDML-settings in translate5 based on the language name and the rfc5646 short-cut in translate5.

The known languages that are possibly available in Indesign need to be mapped already.

The mapping needs to configurable to map more languages.

In the IDML the language is defined at multiple locations as an attribute like this:

AppliedLanguage="$ID/German: Traditional"

The attribute content needs to be changed by Okapi based on the settings.

This is what chatGPT said about possibly existing languages:

Short answer first:

There is no officially published master list from Adobe InDesign, and the set depends on version + installed dictionaries.

However, below is a compiled superset list of all language values that have appeared across CS6 → CC 2024 (including ME and CJK versions). This represents the complete universe of values known to exist in any InDesign installation.

All values follow this exact pattern:

$ID/<Language Name>

✅ Complete Superset of AppliedLanguage Values

English

{{$ID/English: USA
$ID/English: UK
$ID/English: Canadian
$ID/English: Australian
$ID/English: New Zealand
$ID/English: Irish
$ID/English: South Africa}}

German

{{$ID/German: 1996 Reform
$ID/German: Traditional
$ID/Swiss German
$ID/German: Austrian}}

French

{{$ID/French
$ID/French: Canadian
$ID/French: Swiss}}

Spanish

{{$ID/Spanish
$ID/Spanish: Traditional Sort
$ID/Spanish: Modern Sort
$ID/Spanish: Mexican}}

Portuguese

{{$ID/Portuguese: Brazilian
$ID/Portuguese: European}}

Italian

{{$ID/Italian
$ID/Italian: Swiss}}

Dutch

{{$ID/Dutch
$ID/Dutch: Belgian}}

Scandinavian

{{$ID/Swedish
$ID/Danish
$ID/Norwegian: Bokmal
$ID/Norwegian: Nynorsk
$ID/Finnish
$ID/Icelandic}}

Slavic Languages

{{$ID/Polish
$ID/Czech
$ID/Slovak
$ID/Slovenian
$ID/Croatian
$ID/Serbian: Latin
$ID/Serbian: Cyrillic
$ID/Bosnian
$ID/Macedonian
$ID/Bulgarian
$ID/Russian
$ID/Ukrainian
$ID/Belarusian}}

Baltic

{{$ID/Estonian
$ID/Latvian
$ID/Lithuanian}}

Balkan / Southeast Europe

{{$ID/Romanian
$ID/Albanian}}

Central / Western Europe

{{$ID/Hungarian
$ID/Turkish
$ID/Greek}}

Middle Eastern (ME Version)

{{$ID/Arabic
$ID/Arabic: Saudi Arabia
$ID/Arabic: Egypt
$ID/Hebrew
$ID/Farsi
$ID/Urdu}}

Indic (limited support versions)

{{$ID/Hindi
$ID/Bengali
$ID/Tamil
$ID/Telugu
$ID/Marathi
$ID/Gujarati
$ID/Punjabi
$ID/Malayalam
$ID/Kannada}}

East Asian (CJK Versions)

{{$ID/Japanese
$ID/Chinese: Simplified
$ID/Chinese: Traditional
$ID/Chinese: Hong Kong
$ID/Korean}}

Southeast Asian

{{$ID/Thai
$ID/Vietnamese
$ID/Indonesian
$ID/Malay
$ID/Tagalog}}

African Languages (limited availability)

{{$ID/Afrikaans
$ID/Swahili}}

Other Supported Languages (Hunspell-based builds)

{{$ID/Catalan
$ID/Basque
$ID/Galician
$ID/Welsh
$ID/Scottish Gaelic
$ID/Breton
$ID/Luxembourgish
$ID/Maltese}}

⚠ Important Technical Notes

1. The exact spelling must match exactly (case-sensitive in XML).

1. If a language is not installed, InDesign substitutes the default document language.

1. Not all installations contain all dictionaries.

1. Some regional variants exist only in localized builds.

🔎 Absolute Edge Cases

Very old versions (CS3–CS5) and some enterprise builds have also shown:

{{$ID/English: USA Medical
$ID/English: USA Legal}}

(rare, legacy Proximity dictionary builds)

Final Statement

The list above is the full known superset across all publicly released InDesign versions and language packs.

There are no hidden “secret” language identifiers beyond these — every AppliedLanguage value corresponds to a dictionary module shipped with a specific InDesign build.

If you'd like, I can also:

• Generate a validation regex for all possible values

• Provide a normalized canonical language mapping table

• Provide ISO → $ID/ mapping for automation

• Generate a machine-readable JSON list

Just tell me your use case.