diff --git a/tools/tts_tool.py b/tools/tts_tool.py
index e05d1efef..962ed47a0 100644
--- a/tools/tts_tool.py
+++ b/tools/tts_tool.py
@@ -239,6 +239,7 @@ def _generate_openai_tts(text: str, output_path: str, tts_config: Dict[str, Any]
     oai_config = tts_config.get("openai", {})
     model = oai_config.get("model", DEFAULT_OPENAI_MODEL)
     voice = oai_config.get("voice", DEFAULT_OPENAI_VOICE)
+    base_url = oai_config.get("base_url", "https://api.openai.com/v1")
 
     # Determine response format from extension
     if output_path.endswith(".ogg"):
@@ -247,7 +248,7 @@ def _generate_openai_tts(text: str, output_path: str, tts_config: Dict[str, Any]
         response_format = "mp3"
 
     OpenAIClient = _import_openai_client()
-    client = OpenAIClient(api_key=api_key, base_url="https://api.openai.com/v1")
+    client = OpenAIClient(api_key=api_key, base_url=base_url)
     response = client.audio.speech.create(
         model=model,
         voice=voice,
diff --git a/website/docs/user-guide/features/voice-mode.md b/website/docs/user-guide/features/voice-mode.md
index b0f203556..b52286b87 100644
--- a/website/docs/user-guide/features/voice-mode.md
+++ b/website/docs/user-guide/features/voice-mode.md
@@ -404,6 +404,7 @@ tts:
   openai:
     model: "gpt-4o-mini-tts"
     voice: "alloy"                 # alloy, echo, fable, onyx, nova, shimmer
+    base_url: "https://api.openai.com/v1"  # optional: override for self-hosted or OpenAI-compatible endpoints
   neutts:
     ref_audio: ''
     ref_text: ''