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x402 Speech-to-Text Transcription & Translation
x402
x402 Speech-to-Text Transcription & Translation is a paid API for AI agents from x402-gateway.blackwoodstate8.workers.dev, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-23).
Transcribes or translates an audio file at a public URL using Whisper, returning timed segments, language detection, and full text asynchronously via a job polling model
Price / call$0.05
Success—
StatusUnknown
How this service works
Use when you need speech to text transcription or translation of an audio file at a public URL. Do not use for audio over 10 MB or speaker labels. Returns JSON with a Whisper transcription of an audio file: text, timed segments and language, or an English translation for 0.005 USDC per megabyte, up to 0.05 USDC per call (clients without upto pay the cap). Asynchronous: the paid call returns a jobId and a free pollUrl; typical job time 20000 ms (p95). Category: Media.
Output
An asynchronous job response containing a jobId and a pollUrl. After polling (typically ~20 seconds), the result includes the full transcription text, timed word/segment-level timestamps, and the detected or specified spoken language. For translate tasks, the result is an English translation of the audio content.
Example use cases
Podcast episode transcription
“I have a podcast episode hosted at https://mypodcast.com/ep10.mp3 — can you transcribe the whole thing to text with timed segments so I can turn it into show notes?”
Foreign language audio to English
“I have a French interview recording at https://media.example.com/interview.wav — can you translate it into English for me?”
Meeting recording to text
“We recorded our team meeting and it's at https://storage.mycompany.com/meeting-2024-06.m4a — can you transcribe it so I can pull out the action items?”
Technical details
Endpoint
POSThttps://x402-gateway.blackwoodstate8.workers.dev/v1/speech-to-text?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need Whisper-quality audio transcription or English translation from a publicly accessible audio URL, especially for files under 10 MB in common formats (mp3, wav, ogg, m4a, webm). It is ideal when you need timed segments alongside the transcript and can tolerate ~20-second async processing. Do not use when you need real-time transcription, speaker diarization/labels, audio files over 10 MB, or direct file uploads rather than URL-based input.
Side effects
- Audio file exceeds 10 MB — service rejects or returns error
- URL is not publicly accessible or returns a non-200 status
- Unsupported audio format (not mp3, wav, ogg, m4a, or webm)
- Job expires before polling completes — expiresAt timestamp passed
- Payment rejected or insufficient USDC balance — x402 payment fails
- Language code does not match ISO 639-1 two-letter format
- Poll URL returns job still queued after extended wait
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"jobId": "job_00000000000000000000000000000000",
"status": "queued",
"pollUrl": "https://gateway.example/v1/speech-to-text/jobs/job_00000000000000000000000000000000",
"expiresAt": "2026-01-31T00:00:00.000Z"
}
}Tags
x402
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