AI Voice Generator API — Gemini TTS by Google.
Create natural, human-like voices with Gemini TTS at 
Note
If you want a full editor, consider GeminiGen AI Voice Generator - a web app makes video creation and editing effortless, with powerful AI options, intuitive tools, and a clean, user-friendly interface designed for everyone. Along with a dedicated platform that lets users with API access generate text to speech effortlessly.
Gemini TTS is Google’s most advanced and versatile text-to-speech model. It enables you to generate and customize natural, human-like voices seamlessly through simple input, blending studio-quality audio with expressive flexibility.
With this state-of-the-art model at the core, our app unlocks a suite of powerful tools designed to make audio production effortless and inspiring:
- 🎙️ Two Powerful Models — Choose between Gemini 2.5 Flash (fast & efficient) and Gemini 2.5 Pro (higher quality, expressive voices).
- 📝 Text & Document to Speech — Instantly convert text or full documents into natural-sounding audio.
- 💬 AI Dialogue Generation — Build multi-speaker conversations by adding multiple dialogue blocks, each assigned to a different voice. Perfect for creating roleplays, interviews, podcasts, or dramatized storytelling.
- 🔊 Multiple Voice Sources — Use Gemini Voices (AI voices), System Voices (native device voices), or even Your Own Custom Voices.
- 🎭 Custom Prompt Control — Go beyond presets and define your own custom vocal instructions (e.g., soft whisper, news anchor style, bedtime story tone) to fine-tune the output exactly as you need.
- 😊 Emotion & Style Control — Select from presets (Casual, Excited, Firm, Informative, etc.) or define a custom prompt for fine-grained vocal expression.
- 🌍 400+ AI Voices — Wide variety of accents, tones, genders, and styles across different languages and countries.
- ⚡ Speed Adjustment — Fine-tune playback from 0.25x up to 4x for perfect pacing.
- 🎧 Multiple Output Formats — Export to MP3 or WAV for maximum compatibility.
- ⭐ Voice Favorites & Management — Save your own preferred voices and reuse them easily.
- 📊 Real-Time Credit Cost Estimate — See exactly how many credits your generation will use before you hit “Generate Speech”.
- 🔗 Developer-Friendly API — Simple endpoints to control model, emotion, text, speed, format, and voice selection.
- Choose Model — Select between Gemini 2.5 Flash (fast, cost-efficient) or Gemini 2.5 Pro (expressive, high-quality).
- Enter Text — Type or paste up to 30,000 characters into the text box.
- Select Emotion & Style — Pick from presets (Casual, Excited, Firm, Informative, etc.) or use a Custom Prompt for advanced tone control.
- Pick a Voice — Browse Gemini Voices, System Voices, or your Saved Custom Voices.
- Adjust Speed — Fine-tune playback speed from 0.25x to 4x.
- Select Output Format — Choose MP3 or WAV for download.
- Check Credits & Cost — The UI displays cost per character.
- Generate Speech — Click Generate Speech to synthesize your audio. The file will be available for playback or download.
- Choose Model — Select Gemini 2.5 Flash or Gemini 2.5 Pro depending on your needs (speed vs. quality).
- Upload Document — Drag & drop or click to upload supported files: DOCX, XLSX, PPTX, PDF, EPUB, MOBI, TXT, HTML, ODT, ODS, ODP, AZW, AZW3, ...
- Pick a Voice — Choose from Gemini Voices, System Voices, or your Saved Custom Voices.
- Adjust Speed — Set reading pace from 0.25x to 4x.
- Select Output Format — Export the narration as MP3 or WAV.
- Check Credits & Cost — The system shows exact credit usage before generating.
- Generate Speech — Hit Generate Speech and your document will be converted into high-quality spoken audio.
- Choose Model — Pick between Gemini 2.5 Flash or Gemini 2.5 Pro depending on your use case.
- Assign Voices — Select Voice 1, Voice 2 from the Gemini Voices list.
- Add Dialogue Blocks — Each block is tied to a specific voice (e.g., Voice 1, Voice 2).
- Enter Dialogues — Type the spoken lines for each voice in their respective blocks.
- Customize Emotion & Style — Apply presets or use a Custom Prompt (e.g., whispering, news anchor style, bedtime storyteller).
- Adjust Speed — Control playback pacing between 0.25x and 4x.
- Select Output Format — Export the conversation as MP3 or WAV.
- Check Credits & Cost — Preview exact usage before generating.
- Generate Dialogue — Click Generate to create a multi-speaker audio simulating natural conversation.
- ✍️ Be clear with text: Write clean, well-punctuated sentences for more natural speech.
- 🎭 Use emotions wisely: Select an emotion (Casual, Excited, Firm, etc.) or a custom prompt to match the mood of your content.
- 🌍 Pick the right voice: Choose voices that fit your audience’s language, accent, and gender preference.
- ⚡ Balance model choice: Use Gemini 2.5 Flash for speed and cost savings, or Gemini 2.5 Pro for expressive, studio-quality narration.
- 🎧 Adjust speed: Fine-tune playback speed (0.25x–4x) to suit audiobooks, learning materials, or fast demos.
- 📄 Leverage Document to Speech: For long content (PDFs, DOCX, EPUB, etc.), upload documents directly instead of copy-pasting text.
See the power of AI text-to-speech (TTS) in action. Easily generate natural, expressive speech from any text with customizable voices, speeds, and emotions.
We will take the example: convert a short sentence into realistic speech.
Output audio: Listen to audio
Output audio: Listen to audio
We warmly welcome contributions in the form of:
- 💡 Feature Suggestions — Share ideas to improve or expand the app’s capabilities.
- 🛠 Enhancements — Propose improvements to performance, UI/UX, or AI model usage.
- 🐞 Bug Reports — Help us identify and fix issues to ensure a smooth user experience.
- 📈 Collaboration — We are open to discussions about potential partnerships or integrations.
👉 If you’d like to contribute, please reach out via Issues or contact us directly at contact@geminigen.ai
- 👨💻 Our website: https://geminigen.ai
- 📚 Our API Documentation: https://docs.geminigen.ai