Sesame CSM TTS
A 1B conversational speech model that captures natural dialogue timing, turn-taking, and backchannel responses.
Wrap your text in SSML tags for precise control:
<speak><prosody rate="slow">Slow speech</prosody></speak>
Tags the selected model understands — click to drop one into your text where it happens:
This model reads plain text, so inline tags are ignored. For tag-based emotion, switch to an expressive model like Orpheus or Bark.
Define custom pronunciations (word = pronunciation):
About Sesame CSM
Sesame CSM (Conversational Speech Model) is a 1-billion-parameter model from Sesame designed specifically for the rhythms of human conversation. Built on a Llama backbone paired with an audio codec, it models turn-taking timing, backchannel responses (the small acknowledgements people make while listening), emotional reactions, and overall conversational flow. The result reads less like read-aloud text and more like a real spoken exchange. It is a natural fit for AI assistants, chatbots, and conversational interfaces where the goal is speech that feels responsive and human. CSM is released under Apache 2.0, and access on TTS.ai requires a Hugging Face token at the model level.
Best for: AI assistants, chatbots, conversational AI applications
Browse all Sesame CSM voicesAt a glance
- Developer
- Sesame
- License
- Apache 2.0
- Tier
- premium
- Speed
- slow
- Voice cloning
- No
- Languages
- English
- Max characters
- 500