---
title: "Transcribe audio to text"
method: POST
path: "/api/ai/{project_id}/transcribe"
tags: ["AI"]
---

# Transcribe audio to text

`POST /api/ai/{project_id}/transcribe`

## Request

- Base URL: `https://core.blink.new`
- URL: `https://core.blink.new/api/ai/{project_id}/transcribe`
- Auth: HTTP bearer

Transcribe audio to text using Whisper. Accepts a URL, base64 string, or binary buffer. Language is auto-detected; pass `language` (ISO 639-1) to override. Set `timestamp_granularities` to `["word"]` or `["segment"]` for timestamped output.

## Path parameters

- `project_id` string, required

## Request body

- TranscriptionRequest
  - `model` string
  - `audio` union, required
    - string: Base64 encoded audio or URL
    - number[]: Audio buffer as array
  - `language` string: ISO 639-1 language code
  - `response_format` 'json' | 'text' | 'srt' | 'verbose_json' | 'vtt'

## Response `200`

Audio transcription successful

- TranscriptionResponse
  - `result` object: The response data
    - `text` string: Transcribed text content
    - `transcript` string: Transcribed text content (alias for text)
    - `segments` object[]: Detailed transcription segments
      - `id` integer
      - `seek` number
      - `start` number
      - `end` number
      - `text` string
      - `tokens` integer[]
      - `temperature` number
      - `avg_logprob` number
      - `compression_ratio` number
      - `no_speech_prob` number
    - `language` string: Detected or specified language
    - `duration` number: Audio duration in seconds
    - `words` object[]: Word-level timestamps (when requested)
      - `word` string
      - `start` number
      - `end` number
  - `metadata` object
    - `projectId` string: Project identifier
    - `timestamp` string, date-time: Response timestamp
    - `provider` 'google-gemini' | 'openai': AI provider used for generation

## Other responses

- `400`: Validation error
- `401`: Authentication required or invalid API key
- `500`: Internal server error
- `503`: Transcription service not configured

---

[API](https://skmtc.dev/blink/apis/blink-apis.md) - [All operations](https://skmtc.dev/blink/apis/blink-apis/llms.txt) - [OpenAPI document](https://skmtc.dev/blink/apis/blink-apis/revisions/4c59c706078e?raw)