Gemini 3.1 Flash TTS

2026-04-15 · Source: Simon Willison's Weblog · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Software Development & Engineering · Depth: Novice, quick

Summary

The Gemini 3.1 Flash TTS tool, released on April 15, 2026, enables users to convert text into natural-sounding speech using Google's Gemini 3.1 Flash TTS model. This tool supports both single-speaker and multi-speaker conversation modes, offering flexibility for various audio generation needs. Users can customize voice selections and incorporate directorial tags such as `[whisper]` and `[short pause]` to enhance the dynamic delivery of the generated speech. The output audio can be downloaded as a WAV file. Access to the tool requires a valid Gemini API key.

Key takeaway

For developers building applications requiring dynamic and natural-sounding speech, you should explore the Gemini 3.1 Flash TTS tool. Its support for multi-speaker modes and directorial tags like `[whisper]` offers granular control over audio output, potentially enhancing user experience in conversational AI or content creation. Ensure you have a valid Gemini API key for access.

Key insights

Google's Gemini 3.1 Flash TTS tool offers customizable, multi-speaker text-to-speech with directorial tags.

Principles

• Dynamic speech generation
• API key authentication

Method

Input text, select voice, add directorial tags, generate audio, and download as WAV.

In practice

• Generate multi-speaker conversations
• Add `[whisper]` for emphasis

Topics

• Gemini 3.1 Flash TTS
• Text-to-Speech
• Google Gemini API
• Audio Generation
• Multi-speaker Synthesis

Best for: Machine Learning Engineer, AI Engineer, Software Engineer, NLP Engineer

Related on AIssential

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• Build Human-Like AI Voice App with Gemini 3.1 Flash TTS — Gemini 3.1 Flash TTS offers advanced emotional and multi-character voice direction, setting a new benchmark for expressive AI speech.
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Editorial summary, takeaway, and curation by AIssential. Original article published by Simon Willison's Weblog.