v1.22.1

Changed

• Relaxed client-side validation for translation requests using glossaries without a set source language. API-side enforcement remains active until upcoming release.

v1.22.0

Added

• Added support for using multiple glossaries in text and document translation
  via the GlossaryIds property (up to 5 glossary IDs) in TextTranslateOptions
  and DocumentTranslateOptions.
• Added support for style rules in document translation via the StyleId
  property in DocumentTranslateOptions.
• Added support for translation memories in document translation via the
  TranslationMemoryId and TranslationMemoryThreshold properties in
  DocumentTranslateOptions.
• Added support for the translation memory management endpoints in the
  DeepLClient class: GetTranslationMemoryAsync(),
  ListTranslationMemorySegmentsAsync(), DeleteTranslationMemoryAsync(),
  CreateTranslationMemoryImportAsync(), UploadTranslationMemoryFileAsync(),
  CreateTranslationMemoryExportAsync(), GetTranslationMemoryJobAsync(),
  WaitUntilTranslationMemoryJobDoneAsync(),
  DownloadTranslationMemoryExportAsync(),
  ImportTranslationMemoryFromFilepathAsync() and
  ExportTranslationMemoryToFilepathAsync(), along with the
  TranslationMemorySegments, TranslationMemorySegment,
  TranslationMemoryTargetSegment, TranslationMemoryImport,
  TranslationMemoryExport, TranslationMemoryJob and
  TranslationMemoryJobResult model classes.
  Please refer to the README for usage instructions.
• Added the CreationTime and UpdatedTime properties to
  TranslationMemoryInfo.

Fixed

• Fixed incorrect example texts in test suite for several languages (Danish, Indonesian,
  Japanese, Portuguese, and Russian).

v1.21.0

Added

• Added support for translation memories in text translation via
  TranslationMemoryId and TranslationMemoryThreshold properties in
  TextTranslateOptions.
• Added ListTranslationMemoriesAsync() method to the DeepLClient class
  for listing available translation memories.

Fixed

• Fixed gitlab release CI job by explicitly setting the release-cli image to avoid
  issues with a missing $HOME environment variable from the global image.

v1.20.0

Added

• Added new language constants from January 2026 API release of 81 new languages.
• Added ApiPostJsonAsync(), ApiPutJsonAsync(), and ApiPatchJsonAsync() methods to
  DeepLHttpClient, enabling JSON-encoded API calls.
• Added support for style rules CRUD endpoints in the DeepLClient class: CreateStyleRuleAsync(), GetStyleRuleAsync(), UpdateStyleRuleNameAsync(), UpdateStyleRuleConfiguredRulesAsync(), and DeleteStyleRuleAsync().
• Added support for style rule custom instruction CRUD endpoints in the DeepLClient class: CreateStyleRuleCustomInstructionAsync(), GetStyleRuleCustomInstructionAsync(), UpdateStyleRuleCustomInstructionAsync(), and DeleteStyleRuleCustomInstructionAsync().
  Please refer to the README for usage instructions.

v1.19.0

Added

• Added TagHandlingVersion parameter to TextTranslateOptions to specify which version of the tag handling algorithm to use. Options are v1 and v2.

v1.18.0

Added

• Added CustomInstructions property to TextTranslateOptions 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 CustomInstructions parameter will use quality_optimized model type as the default. Requests combining CustomInstructions and the LatencyOptimized model type will be rejected.

v1.17.0

Added

• Added support for style rules in text translation via the StyleId property in TextTranslateOptions.
• Added GetAllStyleRulesAsync() method to DeepLClient to retrieve all available style rules with optional pagination and detailed configuration.
• Added new model classes: StyleRuleInfo, ConfiguredRules, and CustomInstruction to support style rules functionality.

v1.16.0

Added

• Added ExtraBodyParameters option to text and document translation methods to pass arbitrary parameters in the request body. This can be used to access beta features or override built-in parameters (such as target_lang, source_lang, etc.).

v1.15.0

Added

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

v1.14.0

Added

• Added support for the output_format parameter when translating documents.
  • #50 thanks for JuergenRB