Deepgram Speech-to-Text (Nova-3, Flux) vs Google Cloud Speech-to-Text

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.

Google Cloud Speech-to-Text

Audio isn't stored or used for training unless the project opts in to data logging. No release note since 2025-11-13.

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

Google Cloud Speech-to-Text

1. Call Chirp 3 on the us or eu endpoint. It isn't listed for the global location
2. Reopen streams before the 5-minute limit, or use BatchRecognize for recordings
3. Downmix stereo unless you need channel labels, since each channel is billed
4. Set dynamic batch on offline jobs to cut the price from $0.016 to $0.003 a minute
5. Back off on RESOURCE_EXHAUSTED. The Speech docs don't give a retry interval