diff --git a/DeepL/DocumentTranslateOptions.cs b/DeepL/DocumentTranslateOptions.cs
index d24101e..273cef2 100644
--- a/DeepL/DocumentTranslateOptions.cs
+++ b/DeepL/DocumentTranslateOptions.cs
@@ -26,5 +26,8 @@ public DocumentTranslateOptions(GlossaryInfo glossary) : this() {
 
     /// <summary>Specifies the ID of a glossary to use with the translation.</summary>
     public string? GlossaryId { get; set; }
+
+    /// <summary>File extension of desired format of translated file, for example: docx. If unspecified, by default the translated file will be in the same format as the input file.</summary>
+    public string? OutputFormat { get; set; }
   }
 }
diff --git a/DeepL/Translator.cs b/DeepL/Translator.cs
index f609193..a501336 100644
--- a/DeepL/Translator.cs
+++ b/DeepL/Translator.cs
@@ -629,6 +629,10 @@ public async Task<DocumentHandle> TranslateDocumentUploadAsync(
             options?.Formality,
             options?.GlossaryId);
 
+      if (options?.OutputFormat != null) {
+        bodyParams.Add(("output_format", options?.OutputFormat!));
+      }
+
       using var responseMessage = await _client.ApiUploadAsync(
                   "/v2/document",
                   cancellationToken,
diff --git a/README.md b/README.md
index dea989d..f0ec0ce 100644
--- a/README.md
+++ b/README.md
@@ -203,6 +203,7 @@ application needs to execute these steps individually, you can instead use the f
 
 - `Formality`:  same as in [Text translation options](#text-translation-options).
 - `GlossaryId`:  same as in [Text translation options](#text-translation-options).
+- `OutputFormat`: using the parameter during document upload, you can select alternative output formats. See the [API documentation][api-docs-outputformat-param] for more information and example usage.
 
 ### Glossaries
 
@@ -467,6 +468,8 @@ terminal while executing the tests. Execute the tests using `dotnet test` with t
 
 [api-docs-glossary-lang-list]: https://www.deepl.com/docs-api/managing-glossaries/?utm_source=github&utm_medium=github-dotnet-readme
 
+[api-docs-outputformat-param]: https://www.deepl.com/docs-api/documents/format-conversions/?utm_source=github&utm_medium=github-dotnet-readme
+
 [api-docs-xml-handling]: https://www.deepl.com/docs-api/handling-xml/?utm_source=github&utm_medium=github-dotnet-readme
 
 [issues]: https://www.github.com/DeepLcom/deepl-dotnet/issues