Deepgram Speech-to-Text (Nova-3, Flux) vs ElevenLabs Scribe Speech to Text API

Deepgram Speech-to-Text (Nova-3, Flux)

Flux streams with model-level end-of-turn detection, so a voice agent needs no separate VAD. Training on audio is the default and the opt-out is a per-request flag.

ElevenLabs Scribe Speech to Text API

$0.22 an hour for batch with 90+ languages and diarisation to 32 speakers. Audio may be used for training unless the account opts out, and the opt-out isn't retroactive.

Deepgram Speech-to-Text (Nova-3, Flux)

1. Add mip_opt_out=true to every request that carries customer audio
2. Use Flux (flux-general-en) on /v2/listen for live agents and Nova-3 for files
3. Back off exponentially on 429. The concurrency limit is per project
4. Pass callback for long files so the request doesn't hit the 10-minute processing timeout
5. Mint keys with an expiry for short-lived jobs

ElevenLabs Scribe Speech to Text API

1. Create a key restricted to speech-to-text with a credit quota and an expiry
2. Use source_url for hosted files instead of downloading and re-uploading
3. Set webhook=true for long files so the call doesn't block
4. Back off exponentially on any of the three 429 codes
5. Opt out under Data use before sending customer audio. It only covers later uploads