Gemini 3.8 TTS Playground

星海拾光AI 前沿📡 Simon Willison's Weblog2026-09-241004 阅读💛 106 收藏

23rd September 2026

Tool Gemini 3.8 TTS Playground — Test and experiment with Google's Gemini 3.8 text-to-speech API through an interactive playground where you can compose single-voice narration or multi-speaker conversations, preview the generated audio, and explore request and response details. Save your compose settings to bookmarkable URLs for easy sharing, and generate high-quality speech synthesis powered by your Gemini API key.

Google released two new Gemini text-to-speech models today - gemini-3.8-flash-tts and gemini-3.8-flash-lite-tts.

They come with a library of over 2,000 voices, plus the ability to create a custom voice with "just a 30-second audio sample of your voice or a voice you have the rights to use".

I vibe coded this bring-your-own-key playground interface with GPT-6 Astra, taking advantage of the open CORS policy of the underlying Gemini API.

A notable feature of the API is that it makes it easy to define a full conversation between multiple characters, each with different voices and voice style instructions.

Here's a short demo clip of a conversation between two pelicans debating if they should move to the Pacifica Pier. I had Claude 4.5 Opus write the script and generate a URL to render it using the tool.

Your browser does not support the audio element.

It took ~20 seconds to generate 1m 18s of audio using Gemini 3.8 Flash TTS (not the cheaper Flash-Lite), at a cost of 2.74 cents.

Posted 23rd September 2026 at 5:12 pm