REST API

Use any ASR backend via HTTP API (local or cloud).

Cohere 🇨🇦

Sign up at dashboard.cohere.com — Canadian-hosted, same as local Apache 2.0 model.

• Cohere Transcribe — #1 Open ASR Leaderboard, 5.42 avg WER, 14 languages

Note: Cohere’s API requires a language parameter. Set "language": "en" (or your language code) in your config alongside the backend selection.

OpenAI

Bring an API key from OpenAI, and choose from:

• GPT-4o Transcribe - Latest model with best accuracy
• GPT-4o Mini Transcribe - Faster, lighter model
• GPT-4o Mini Transcribe (2025-12-15) - Updated version of the faster, lighter transcription model
• GPT Audio Mini (2025-12-15) - General purpose audio model
• Whisper 1 - Legacy Whisper model

Groq

Bring an API key from Groq, and choose from:

• Whisper Large V3 - High accuracy processing
• Whisper Large V3 Turbo - Fastest transcription speed

Regolo

Bring an API key from Regolo, European-hosted with zero data retention (GDPR):

• Faster Whisper Large V3 - High accuracy, zero data retention (GDPR)

Custom backend

Connect to any backend, local or cloud, via your own custom configuration:

{
    "transcription_backend": "rest-api",
    "rest_endpoint_url": "https://your-server.example.com/transcribe",
    "rest_fallback_endpoint_urls": [      // optional ordered fallback endpoints
        "https://fallback.example.com/v1/audio/transcriptions"
    ],
    "rest_headers": {                     // optional arbitrary headers
        "authorization": "Bearer your-api-key-here"
    },
    "rest_body": {                        // optional body fields merged with defaults
        "model": "custom-model"
    },
    "rest_api_key": "your-api-key-here",  // equivalent to rest_headers: { authorization: Bearer your-api-key-here }
    "rest_timeout": 30,                   // optional, default: 30; per endpoint
    "rest_audio_format": "wav"            // optional audio format sent to the endpoint: "wav" (default) | "mp3"
}

rest_fallback_endpoint_urls are mirrors of the primary, tried in order. They get the same key, headers and body. Failover happens only when an endpoint can’t be reached or answers 429 or 5xx. Behind a keyed https:// primary, http:// fallbacks are skipped.