Gemini TTS

Gemini TTS (Text-to-Speech) is Google's speech synthesis technology that turns written sentences into audio that sounds like a real person speaking.

Think of it like a voice actor reading from a script — except an AI plays that role instead of a human actor. You feed in a sentence, and it produces audio with natural intonation and pronunciation. You can even specify the tone, asking it to read cheerfully or calmly.

This technology isn't limited to reading out announcements. Recently, it's also been used to interrupt mid-conversation or shift intonation the way a real person would, which makes it useful for generating simulated user voices when testing voice-based conversational AI agents.

In articles, you might see it described like: 'A simulated user generates audio with Gemini TTS in a real voice and speaks to the agent.' It's important not to confuse Gemini TTS with the AI 'brain' that comes up with what to say — it's a voice output tool that converts already-decided text into sound.

If you have access to Google Gemini's text-to-speech feature, try specifying different tones for the same sentence and compare the results.

• 'Read the following sentence in a calm, low tone: The meeting starts at 3 PM.'
• 'Read the following sentence in a bright, upbeat tone: The meeting starts at 3 PM.'

Listening to how the intonation and pace change with the tone you specify — even for the same sentence — gives you an immediate sense of what this technology does.