Gemini 3.8 TTS Playground
Google released two Gemini text-to-speech models, gemini-3.8-flash-tts and gemini-3.8-flash-lite-tts, according to Simon Willison. The models ship with a library of over 2,000 voices and support creating a custom voice from a 30-second audio sample of a voice the user has the rights to use.
Willison wrote that he built a bring-your-own-key playground interface for the models with GPT-6 Astra, using the open CORS policy of the underlying Gemini API. He described the API as making it easy to define a full conversation between multiple characters, each with different voices and voice style instructions.
As a demonstration, he cited a short clip of a conversation between two pelicans debating whether they should move to the Pacifica Pier. He said Claude 4.5 Opus wrote the script and generated a URL to render it using the tool.
Willison reported that generating 1 minute 18 seconds of audio with Gemini 3.8 Flash TTS, not the cheaper Flash-Lite, took about 20 seconds and cost 2.74 cents.
The tool is tagged under text-to-speech and Gemini.
Based on reporting from the original publisher. Visit the source for full context and later updates.
Publisher excerpt
Tool: Gemini 3.8 TTS Playground 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