OpenAI · Transcription model

Whisper 1

openai/whisper-1

Transcription

Released Apr 27, 2026

Whisper is OpenAI's open-source automatic speech recognition model, available via API as `whisper-1`. It supports transcription and translation across 50+ languages from audio files up to 25 MB. Accepts formats...

Specifications

Input: wav, mp3, flac, m4a, ogg, webm, aac, opus · base64 JSON, multipart file or URL · up to 25 MB
Output: text; verbose_json adds language, duration, segments and word timestamps
Billing: per second of audio

Use it

POST /api/v1/audio/transcriptions · MCP transcribe · full reference

curl https://omnirail.org/api/v1/audio/transcriptions \
  -H "Authorization: Bearer $OMNIRAIL_KEY" \
  -F model=openai/whisper-1 \
  -F file=@meeting.mp3