CSM 1B is a conversational speech model from Sesame. It accepts text input and produces English speech output, with voice options spanning conversational and read-speech styles. At 1B parameters, it is suited for dialogue-oriented applications such as voice assistants and interactive agents.
Modalities
Price
$7per 1M characters
Context
4K
Released
Apr 23, 2026
Weekly Tokens
9K
OpenRouter provides a text-to-speech API that converts text into natural-sounding audio. Send text and a voice selection, and receive raw audio bytes in your chosen format.
The response is a raw audio stream (not JSON). The generation ID is returned in the X-Generation-Id response header for tracking.
For information about using third-party SDKs and frameworks with OpenRouter, please see our frameworks documentation.
See the Request docs for all possible fields, and Parameters for explanations of specific sampling parameters.