Gemini-TTS

Text-to-Speech Gemini-TTS is the latest evolution of our Text-to-Speech technology that's moving beyond just naturalness to giving granular control over generated audio using text-based prompts. Using Gemini-TTS, you can synthesize speech from short snippets to long-form narratives, precisely dictating style, accent, pace, tone, and even emotional expression, all steerable through natural-language prompts.

Gemini-TTS capabilities are supported by the following:

gemini-2.5-flash-preview-tts : Gemini 2.5 Flash Preview is good for cost-efficient everyday applications.
gemini-2.5-pro-preview-tts : Gemini 2.5 Pro Preview is good for controllable speech generation (TTS) and for state-of-the-art quality of complex prompts.

Model	Optimized for	Input modality	Output modality	Single speaker
Gemini 2.5 Flash Preview TTS	Low latency, controllable, single- and multi-speaker Text-to-Speech audio generation for cost-efficient everyday applications	Text	Audio	✔️
Gemini 2.5 Pro Preview TTS	High control for structured workflows like podcast generation, audiobooks, customer support, and more	Text	Audio	✔️

Additional controls and capabilities include the following:

Natural conversation: Voice interactions of remarkable quality, more appropriate expressivity, and prosody (patterns of rhythm) are delivered with very low latency so you can converse fluidly.
Style control: Using natural language prompts, you can adapt the delivery within the conversation by steering it to adopt specific accents and produce a range of tones and expressions including a whisper.
Dynamic performance: These models can bring text to life for expressive readings of poetry, newscasts, and engaging storytelling. They can also perform with specific emotions and produce accents when requested.
Enhanced pace and pronunciation control: Controlling delivery speed helps to ensure more accuracy in pronunciation including specific words.

Examples

model: "gemini-2.5-pro-preview-tts"
prompt: "You are having a casual conversation with a friend. Say the following in a friendly and amused way."
text: "hahah I did NOT expect that. Can you believe it!."
speaker: "Callirhoe"

model: "gemini-2.5-flash-preview-tts"
prompt: "Say the following in a curious way"
text: "OK, so... tell me about this [uhm] AI thing.",
speaker: "Orus"

model: "gemini-2.5-flash-preview-tts"
prompt: "Say the following"
text: "[extremely fast] Availability and terms may vary. Check our website or your local store for complete details and restrictions."
speaker: "Kore"

See Use Gemini-TTS section for details on how to use these voices programmatically.

Voice Options

Gemini-TTS offers a wide range of voice options similar to our existing Chirp 3: HD Voices, each with distinct characteristics:

Name	Gender	Demo
Achernar	Female
Achird	Male
Algenib	Male
Algieba	Male
Alnilam	Male
Aoede	Female
Autonoe	Female
Callirrhoe	Female
Charon	Male
Despina	Female
Enceladus	Male
Erinome	Female
Fenrir	Male
Gacrux	Female
Iapetus	Male
Kore	Female
Laomedeia	Female
Leda	Female
Orus	Male
Pulcherrima	Female
Puck	Male
Rasalgethi	Male
Sadachbia	Male
Sadaltager	Male
Schedar	Male
Sulafat	Female
Umbriel	Male
Vindemiatrix	Female
Zephyr	Female
Zubenelgenubi	Male

Language availability

Gemini-TTS offers a wide range of voice options similar to our existing Chirp 3: HD Voices, each with distinct characteristics:

Language	BCP-47 Code
English (United States)	en-US

Regional availability

Gemini-TTS models are available in the following Google Cloud regions respectively:

Google Cloud zone	Launch readiness
`us`	Public Preview

Supported output formats

The default response format is LINEAR16 . Other supported formats include the following:

API method	Format
`batch`	ALAW, MULAW, MP3, OGG_OPUS, and PCM

Use Gemini-TTS

Discover how to use Gemini-TTS models to synthesize single-speaker speech.

Perform synchronous speech synthesis request

Python

  # google-cloud-texttospeech minimum version 2.29.0 is required. 
 import 
  
 os 
 from 
  
 google.cloud 
  
 import 
 texttospeech 
 PROJECT_ID 
 = 
 os 
 . 
 getenv 
 ( 
 "GOOGLE_CLOUD_PROJECT" 
 ) 
 def 
  
 synthesize 
 ( 
 prompt 
 : 
 str 
 , 
 text 
 : 
 str 
 , 
 model_name 
 : 
 str 
 , 
 output_filepath 
 : 
 str 
 = 
 "output.mp3" 
 ): 
  
 """Synthesizes speech from the input text and saves it to an MP3 file. 
 Args: 
 prompt: Stylisting instructions on how to synthesize the content in 
 the text field. 
 text: The text to synthesize. 
 model_name: Gemini model to use. Currently, the available models are 
 gemini-2.5-flash-preview-tts and gemini-2.5-pro-preview-tts 
 output_filepath: The path to save the generated audio file. 
 Defaults to "output.mp3". 
 """ 
 client 
 = 
 texttospeech 
 . 
  TextToSpeechClient 
 
 () 
 synthesis_input 
 = 
 texttospeech 
 . 
  SynthesisInput 
 
 ( 
 text 
 = 
 text 
 , 
 prompt 
 = 
 prompt 
 ) 
 # Select the voice you want to use. 
 voice 
 = 
 texttospeech 
 . 
  VoiceSelectionParams 
 
 ( 
 language_code 
 = 
 "en-US" 
 , 
 name 
 = 
 "Charon" 
 , 
 # Example voice, adjust as needed 
 model_name 
 = 
 model_name 
 ) 
 audio_config 
 = 
 texttospeech 
 . 
  AudioConfig 
 
 ( 
 audio_encoding 
 = 
 texttospeech 
 . 
  AudioEncoding 
 
 . 
 MP3 
 ) 
 # Perform the text-to-speech request on the text input with the selected 
 # voice parameters and audio file type. 
 response 
 = 
 client 
 . 
  synthesize_speech 
 
 ( 
 input 
 = 
 synthesis_input 
 , 
 voice 
 = 
 voice 
 , 
 audio_config 
 = 
 audio_config 
 ) 
 # The response's audio_content is binary. 
 with 
 open 
 ( 
 output_filepath 
 , 
 "wb" 
 ) 
 as 
 out 
 : 
 out 
 . 
 write 
 ( 
 response 
 . 
 audio_content 
 ) 
 print 
 ( 
 f 
 "Audio content written to file: 
 { 
 output_filepath 
 } 
 " 
 )

CURL

  # Make sure to install gcloud cli, and sign in to your project. 
 # Make sure to use your PROJECT_ID value. 
 # Currently, the available models are gemini-2.5-flash-preview-tts and gemini-2.5-pro-preview-tts 
 # To parse the JSON output and use it directly see the last line of the command. 
 # Requires JQ and ffplay library to be installed. 
 PROJECT_ID 
 = 
 YOUR_PROJECT_ID 
curl  
-X  
POST  
 \ 
-H  
 "Authorization: Bearer 
 $( 
gcloud  
auth  
application-default  
print-access-token ) 
 " 
  
 \ 
-H  
 "x-goog-user-project: 
 $PROJECT_ID 
 " 
  
 \ 
-H  
 "Content-Type: application/json" 
  
 \ 
-d  
 '{ 
 "input": { 
 "prompt": "Say the following in a curious way", 
 "text": "OK, so... tell me about this [uhm] AI thing." 
 }, 
 "voice": { 
 "languageCode": "en-us", 
 "name": "Kore", 
 "model_name": "gemini-2.5-flash-preview-tts" 
 }, 
 "audioConfig": { 
 "audioEncoding": "LINEAR16" 
 } 
 }' 
  
 \ 
 "https://texttospeech.googleapis.com/v1/text:synthesize" 
  
 \ 
 | 
  
jq  
-r  
 '.audioContent' 
  
 | 
  
base64  
-d  
 | 
  
ffplay  
-  
-autoexit