API Documentation

Authentication

All API requests must include your API key in the Authorization header as a Bearer token.

curl https://captaintranscribe.com/api/v1/transcriptions \
  -H "Authorization: Bearer ct_your_api_key_here"

Your API key starts with ct_. Keep it secret -- do not expose it in client-side code.

POST /api/v1/transcribe

Transcribe an audio or video file. This is a synchronous endpoint -- the response is returned once transcription completes.

Request

Send a multipart/form-data request with the following fields:

Example

curl -X POST https://captaintranscribe.com/api/v1/transcribe \
  -H "Authorization: Bearer ct_your_api_key_here" \
  -F "[email protected]" \
  -F "language=fr" \
  -F "speakerDetection=true"

Response

{
  "id": "abc123",
  "text": "Full transcription text...",
  "segments": [
    { "start": 0.0, "end": 3.5, "text": "Hello world" }
  ],
  "words": [
    { "start": 0.0, "end": 0.5, "word": "Hello" },
    { "start": 0.6, "end": 1.0, "word": "world" }
  ],
  "language": "en",
  "duration": 125.4,
  "speakers": [
    {
      "label": "A",
      "segments": [{ "start": 0.0, "end": 3.5, "text": "Hello world" }]
    }
  ]
}

The speakers field is only present when speaker detection is enabled. The X-RateLimit-Remaining header indicates remaining quota minutes.

GET /api/v1/transcriptions

List your transcriptions with pagination.

Query Parameters

Example

curl https://captaintranscribe.com/api/v1/transcriptions?limit=10&offset=0 \
  -H "Authorization: Bearer ct_your_api_key_here"

Response

{
  "transcriptions": [
    {
      "id": "abc123",
      "fileName": "interview.mp3",
      "language": "fr",
      "duration": 125.4,
      "createdAt": "2026-04-01T10:30:00.000Z"
    }
  ],
  "limit": 10,
  "offset": 0,
  "count": 1
}

GET /api/v1/transcription/:id

Get the full transcription result by ID.

Example

curl https://captaintranscribe.com/api/v1/transcription/abc123 \
  -H "Authorization: Bearer ct_your_api_key_here"

Response

{
  "id": "abc123",
  "text": "Full transcription text...",
  "segments": [...],
  "words": [...],
  "language": "fr",
  "duration": 125.4
}

Rate Limits

The X-RateLimit-Remaining response header shows your remaining quota minutes after each transcription.

Error Handling

All errors return a JSON object with an error field.

Example error response

{
  "error": "Monthly quota exceeded"
}