v1.29.0

Added

• Added new language constants from January 2026 API release of 81 new languages.
• Added support for style rules CRUD endpoints in the DeepLClient class:
  create_style_rule(), get_style_rule(), update_style_rule_name(),
  update_style_rule_configured_rules(), and delete_style_rule().
• Added support for style rule custom instruction CRUD endpoints in the
  DeepLClient class: create_style_rule_custom_instruction(),
  get_style_rule_custom_instruction(),
  update_style_rule_custom_instruction(), and
  delete_style_rule_custom_instruction().
  Please refer to the README for usage instructions.

Changed

• Updated formality tests to accept either formal or informal output when using default formality,
  since the default formality is automatic.

v1.28.0

Changed

• Updated three tests to be less flakey and reflect new behavior regarding the model type.
• Improved NotFoundException error message by removing the misleading "check server_url" suggestion.

Fixed

• Fixed a bug where translating with style rules would sometimes incorrectly result in
  a "target_lang must match style rule language" error

Security

• Updated dependencies to fix CVE-2025-66418 and CVE-2025-66471

v1.27.0

Added

• Added tag_handling_version parameter to translate_text() to specify which version
  of the tag handling algorithm to use. Options are v1 and v2.
• Added an example CLI script for realtime audio translation using DeepL's Voice API.

v1.26.0

Added

• Added custom_instructions parameter to translate_text() to customize translation behavior with up to 10 instructions (max 300 characters each). Only supported for target languages: de, en, es, fr, it, ja, ko, zh and their variants. Note: using the custom_instructions parameter will use the quality_optimized model type as the default. Requests combining custom_instructions and the latency_optimized model type will be rejected.

v1.25.0

• Added support for the GET /v3/style_rules endpoint in the client library, the implementation can be found in the DeepLClient class. Please refer to the README for usage instructions
• Added style_id option to translate_text() which allows text translation with style rules.

v1.24.0

Changed

• extra_body_parameters will now overwrite already set HTTP parameters

v1.23.0

Added

• Added feature to add arbitrary body parameters in translate_text

Deprecated

• Dropped support for Python 3.8 and older.

Security

• Updated requests minimum version to 2.32.4 to resolve security advisories
  CVE-2024-47081 and CVE-2024-35195.

v1.22.0

Added

• Added support for the /v3 Glossary APIs in the client library while providing backwards compatibility for the previous /v2 Glossary endpoints. Please refer to the README for usage instructions.

v.1.21.1

Added

• (beta) optional parameter to specify timeout for document translation calls

v1.21.0

Added

• Added support for the Write API in the client library, the implementation
  can be found in the DeepLClient class. Please refer to the README for usage
  instructions.

Changed

• The main functionality of the library is now also exposed via the DeepLClient
  class. Please change your code to use this over the Translator class whenever
  convenient.