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SesameText to Speech/v1/media/queue

Sesame CSM 1B

Sesame CSM 1B text to speech — conversational speech for assistants, billed on input length.

A conversational speech model whose voices split along a useful axis: conversational voices for dialogue and assistant turns, read-speech voices for narration.

No credit card required. Takes 30 seconds.

2,400+

Developers

1.2M+

API calls served

100+

Endpoints

$0.01

Per call

Yep, that's it.

Playground coming soon — use the API endpoint directly with your API key.

Pricing

Per character: $0.0148/1K chars

Endpoint

/v1/media/queue

Strengths

Conversational vs read-aloud

Voice families are split by purpose, so an assistant turn and a narration passage each get the right delivery.

Built for dialogue

Designed for back-and-forth conversation rather than long monologue.

Small and cheap

At 1B parameters it stays affordable enough for every turn of a conversation.

English-only

Focused on doing one language well.

Quick start

Copy this snippet and start making calls with Sesame CSM 1B.

// Step 1: Submit job
const res = await fetch('https://api.yepapi.com/v1/media/queue', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "sesame/csm-1b",
    "prompt": "Sure — I can do that. Do you want me to send it now, or wait until the rest of the team has signed off?",
    "options": {
      "voice": "conversational_a"
    }
  }),
});
const { data } = await res.json();
const jobId = data.jobId;

// Step 2: Poll for result
const status = await fetch(`https://api.yepapi.com/v1/media/status/${jobId}`, {
  headers: { 'x-api-key': 'YOUR_API_KEY' },
});
const { data: job } = await status.json();
// job.status: "pending" | "processing" | "completed" | "failed"
// job.result: { text?, image?, audio?, video? }

Why use Sesame CSM 1B through YepAPI?

One API key for all models — no separate accounts
No monthly minimums — pay per call
Switch models with one line of code
Simple REST API — works from any language
Unified billing across all providers
No rate limits for most use cases

Sesame CSM 1B API — conversational speech synthesis

CSM 1B is a conversational speech model from Sesame. Its voice options split along a useful axis: `conversational_*` voices for dialogue and assistant turns, `read_speech_*` voices for narration and read-aloud content.

At 1B parameters it stays cheap enough to synthesise every turn of a live conversation. Billed at $0.0148 per 1,000 characters on YepAPI.

Start generating in 30 seconds

$5 free credit on signup. No credit card required. Pay per call.

What developers say

Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.

Marcus T.

SEO Platform Founder

One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.

Priya S.

Full-Stack Developer

The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.

Jake R.

Indie Hacker

Frequently asked questions

A conversational speech model whose voices split along a useful axis: conversational voices for dialogue and assistant turns, read-speech voices for narration.

Pricing for Sesame CSM 1B through YepAPI is based on usage. No monthly minimums — you only pay for what you use.

Sign up for a free API key, then send requests to the /v1/media/queue endpoint.

Ready to use Sesame CSM 1B?

$5 free credit on signup. No credit card required. Pay per call.

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