Google DeepMind Releases Gemini 3.1 Flash TTS with Enhanced Expressiveness and Vocal Tag Controls

Google DeepMind has launched Gemini 3.1 Flash TTS, a new audio model designed to improve the quality and control of AI-generated speech. The model is now available through Google AI Studio, Vertex AI, and Google Vids, providing developers with more sophisticated tools for high-fidelity speech synthesis. This release represents a significant step forward in making AI voices sound more natural and less robotic across diverse applications. A key innovation in this release is the introduction of voice tags, which allow developers to use natural language commands to adjust vocal styles and speaking rates. Supporting over 70 languages, the model enables more expressive audio generation compared to previous iterations. These tags provide a layer of granular control that was previously difficult to achieve without complex manual tuning or specialized datasets. For practical implementation and safety, the model includes SynthID digital watermarking to identify AI-generated content and mitigate the spread of misinformation. While the voice tags offer extensive control, engineers should perform thorough testing to ensure that adjustments to emotional tone and linguistic nuances remain consistent. Fine-tuning may still be required to capture the specific prosody and cultural context of certain languages within the supported list.