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Inference402 Speech-to-Text Transcription
x402
Inference402 Speech-to-Text Transcription is a paid API for AI agents from inference402.worlddata402.workers.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-20).
Transcribes audio from a public URL into text with timestamps and word count using Whisper Large v3 Turbo, paid per-call in USDC via x402.
Price / call$0.02
Success—
StatusUnknown
How this service works
Pay-per-call AI inference for agents: chat (Llama 3.3 70B / 3.1 8B), structured JSON, summarize, translate (incl. Egyptian Arabic), extract, classify, sentiment, keywords, rewrite, embeddings, moderation, vision and speech-to-text. USDC on Base mainnet over x402. No API key, no account.
Output
Returns a JSON object with the full transcribed text, the model used (Whisper Large v3 Turbo), detected or hinted language code, word count, total audio duration in seconds, and an array of timed segments each with start time, end time, and segment text.
Example use cases
Podcast episode transcription
“Can you transcribe this podcast episode for me? The audio is at https://media.example.com/episode42.mp3 and it's in English — I want the full text and segment timestamps.”
Multilingual interview transcription
“I have a recorded interview in Egyptian Arabic at https://storage.example.com/interview.mp3, please transcribe it to text for me with word count and duration.”
Voice memo to text conversion
“Turn this voice memo into text — the audio URL is https://files.example.com/memo.wav, it's in English, and I need the timestamped segments so I can find specific parts later.”
Technical details
Endpoint
GEThttps://inference402.worlddata402.workers.dev/v1/audio/transcribe?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need keywordless, no-account, pay-per-call audio transcription billed in USDC via the x402 protocol, especially when you want Whisper-quality results with timed segments without managing API keys or subscriptions. Ideal for AI agents that need to process audio on demand without prior account setup.
Side effects
- Audio file exceeds 10MB limit — request rejected
- Audio URL is not publicly accessible or returns 4xx/5xx — fetch failure
- Unsupported audio format — transcription fails
- Invalid ISO 639-1 language code provided — may cause incorrect transcription
- Payment not received or insufficient USDC balance — 402 Payment Required
- Transient Cloudflare Workers AI backend error — service unavailable
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| language | string | Optional ISO 639-1 spoken-language hint, e.g. ar |
| audio_url | string | Public http(s) URL of an audio file ≤10MB |
Output
Schema · Response
{
"type": "json",
"example": {
"text": "Hello and welcome ...",
"model": "@cf/openai/whisper-large-v3-turbo",
"language": "en",
"segments": [
{
"end": 4.2,
"text": "Hello and welcome",
"start": 0
}
],
"word_count": 96,
"duration_seconds": 42.1
}
}Tags
x402
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