{"slug": "gemini-3-8-tts-playground", "title": "Gemini 3.8 TTS Playground", "summary": "Google released two new Gemini text-to-speech models, gemini-3.8-flash-tts and gemini-3.8-flash-lite-tts, which ship with a library of over 2,000 voices and can create a custom voice from a 30-second audio sample. Developer Simon Willison built a bring-your-own-key Gemini 3.8 TTS Playground interface using GPT-6 Astra, and reported that generating 1 minute 18 seconds of multi-character audio with Gemini 3.8 Flash TTS took about 20 seconds at a cost of 2.74 cents.", "body_md": "**Tool:** [Gemini 3.8 TTS Playground](https://tools.simonwillison.net/gemini-tts-playground)\n\nGoogle [released two new Gemini text-to-speech models](https://blog.google/innovation-and-ai/models-and-research/gemini-models/gemini-3-8-text-to-speech/) today - `gemini-3.8-flash-tts` and `gemini-3.8-flash-lite-tts`.\n\nThey 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\".\n\nI [vibe coded](https://tools.simonwillison.net/markdown-svg-renderer?url=https%3A%2F%2Fgist.github.com%2Fsimonw%2Fa82f3aef2677c623d1776092d6b21224) this bring-your-own-key playground interface with GPT-6 Astra, taking advantage of the open CORS policy of the underlying Gemini API.\n\nA 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.\n\nHere's a short demo clip of a conversation between two pelicans debating if they should move to [the Pacifica Pier](https://simonwillison.net/2026/Sep/12/sighting-399708714/). I had Claude 4.5 Opus [write the script](https://claude.ai/share/3597fc77-9323-4583-aeb9-b0e4c3f654a3) and generate [a URL to render it using the tool](https://simonwillison.net/u/vj).\n\nIt 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.\n\nTags: [text-to-speech](https://simonwillison.net/tags/text-to-speech), [gemini](https://simonwillison.net/tags/gemini)", "url": "https://wpnews.pro/news/gemini-3-8-tts-playground", "canonical_source": "https://simonwillison.net/2026/Sep/23/gemini-tts-playground/", "published_at": "2026-09-23 17:12:27+00:00", "updated_at": "2026-09-23 20:59:35.266131+00:00", "lang": "en", "topics": ["generative-ai", "ai-products", "ai-tools", "large-language-models"], "entities": ["Google", "Gemini 3.8 TTS Playground", "gemini-3.8-flash-tts", "gemini-3.8-flash-lite-tts", "Simon Willison", "GPT-6 Astra", "Claude 4.5 Opus", "Gemini API"], "alternates": {"html": "https://wpnews.pro/news/gemini-3-8-tts-playground", "markdown": "https://wpnews.pro/news/gemini-3-8-tts-playground.md", "text": "https://wpnews.pro/news/gemini-3-8-tts-playground.txt", "jsonld": "https://wpnews.pro/news/gemini-3-8-tts-playground.jsonld"}}