Index onlineMerchant portal
Api Endpoint

Text-to-speech (4,358 voices)

Text-to-speech (OpenAI-compatible /v1/audio/speech). 4,358 voices across 9 providers (KokoroTTS, AWS Polly, Azure, MiniMax, more — free catalog at GET /v1/audio/voices). Returns mp3. Up to 3000 chars. $0.000006 USDC per character (Telnyx list rate, zero margin): pay per character via the upto scheme (min $0.002 network settlement floor, so ≤333-char calls settle at $0.002), or flat $0.018 exact.

Open interactive test console

Offering

Provider
x402.telnyx.com
Method
POST
Offering type
Api Endpoint
Transport type
http
Category
Creative
Delivery
Not provided
Pricing model
Not provided
x402 version
2

Endpoint context

URL
https://x402.telnyx.com/v1/audio/speech
MIME type
Not provided
First seen
2026-10-16T01:50:19.913Z
Last seen
Tags
AI, text-to-speech, tts, audio, telnyx

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1
0.018 USDC
Atomic price: 18000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Payment option 2
0.018 USDC
Atomic price: 18000 · Network: eip155:8453 · Asset: USDC · Scheme: upto
Raw x402 terms
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "18000",
    "payTo": "0x19a78B27a28eD93C3c914878bde7f2f843AfAEa8"
  },
  {
    "scheme": "upto",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "18000",
    "payTo": "0x19a78B27a28eD93C3c914878bde7f2f843AfAEa8"
  }
]

Observed health

Status
Healthy
Latest latency
92 ms
Average latency
434 ms
HTTP status
200
Last checked
Reachability
100% over 14 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "additionalProperties": false,
  "properties": {
    "body": {
      "properties": {
        "input": {
          "description": "Text to synthesize (max 3000 characters).",
          "maxLength": 3000,
          "minLength": 1,
          "type": "string"
        },
        "model": {
          "description": "Accepted for OpenAI SDK compatibility; the voice id selects the engine.",
          "type": "string"
        },
        "response_format": {
          "enum": [
            "mp3"
          ],
          "type": "string"
        },
        "voice": {
          "description": "OpenAI voice name (alloy, echo, fable, onyx, nova, shimmer, …) or Telnyx voice id (Provider.Model.VoiceId). Full catalog: GET /v1/audio/voices.",
          "type": "string"
        }
      },
      "required": [
        "input",
        "voice"
      ],
      "type": "object"
    },
    "bodyType": {
      "enum": [
        "json",
        "form-data",
        "text"
      ],
      "type": "string"
    },
    "method": {
      "enum": [
        "POST"
      ],
      "type": "string"
    },
    "type": {
      "const": "http",
      "type": "string"
    }
  },
  "required": [
    "type",
    "method",
    "bodyType",
    "body"
  ],
  "type": "object"
}

Output schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "properties": {
    "input": {
      "additionalProperties": false,
      "properties": {
        "body": {
          "properties": {
            "input": {
              "description": "Text to synthesize (max 3000 characters).",
              "maxLength": 3000,
              "minLength": 1,
              "type": "string"
            },
            "model": {
              "description": "Accepted for OpenAI SDK compatibility; the voice id selects the engine.",
              "type": "string"
            },
            "response_format": {
              "enum": [
                "mp3"
              ],
              "type": "string"
            },
            "voice": {
              "description": "OpenAI voice name (alloy, echo, fable, onyx, nova, shimmer, …) or Telnyx voice id (Provider.Model.VoiceId). Full catalog: GET /v1/audio/voices.",
              "type": "string"
            }
          },
          "required": [
            "input",
            "voice"
          ],
          "type": "object"
        },
        "bodyType": {
          "enum": [
            "json",
            "form-data",
            "text"
          ],
          "type": "string"
        },
        "method": {
          "enum": [
            "POST"
          ],
          "type": "string"
        },
        "type": {
          "const": "http",
          "type": "string"
        }
      },
      "required": [
        "type",
        "method",
        "bodyType",
        "body"
      ],
      "type": "object"
    },
    "output": {
      "properties": {
        "example": {
          "type": "object"
        },
        "type": {
          "type": "string"
        }
      },
      "required": [
        "type"
      ],
      "type": "object"
    }
  },
  "required": [
    "input"
  ],
  "type": "object"
}