Google has released Gemini 3.5 Transcribe, a speech-to-text model for real-time voice interfaces and recorded audio. It ships as two endpoints, not one. gemini-3.5-transcribe handles pre-recorded files through the Interactions API. gemini-3.5-transcribe-live handles bidirectional streaming through the Live API. Google reports average word error rates of 4.0% streaming and 2.6% non-streaming, as measured by Artificial Analysis. Time to final transcription improves 70% over Chirp 3, the previous model. Automatic detection covers more than 85 languages, including mid-sentence code-switching. The split between the two endpoints is the part worth planning around. They do not share the same feature set, limits, or price.
Yes, but API-only. There are no open weights and no self-hosted path. This is a managed-service decision, not an infrastructure one.
The Live API delivers sub-second, continuous transcription. It emits interim_input_transcription for speculative partials while someone is still talking, then input_transcription when the turn finalizes. Audio goes in as raw 16-bit PCM at 16kHz mono, in 100ms chunks. It supports automatic, hybrid, and manual voice-activity detection. Ephemeral tokens let mobile and web clients stream without holding an API key.
