AssemblyAI Universal-3.5 Pro (async)
Speech and audio
universal-3-pro
$0.21 per hour
AssemblyAI Universal-3.6 Pro Realtime
Model iduniversal-3-6-pro
Price$0.45 per hour
Checked29 September 2026
Where it stands
13newer speech and audio models since its release
- NVIDIA Nemotron 3.5 Transcribe (30B-A4B)28 Oct 2026
- Hy-SimulMT-30B-A3B22 Oct 2026
- Eleven Realtime v1 Max / Mini20 Oct 2026
- Voxtral Mini Transcribe 3 (+ Mini Transcribe Realtime 3)20 Oct 2026
- Voxtral Small Transcribe 320 Oct 2026
The 5 newest are listed. All speech and audio models
- Before it from AssemblyAI
- AssemblyAI Universal-3.5 Pro (async)7 Jul 2026
- Weights
- Closed weights; access is hosted only.
How to call it
2 ways to use AssemblyAI Universal-3.6 Pro Realtime, with the model id each provider expects.
| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| AssemblyAI API | universal-3-6-pro |
wss://streaming.assemblyai.com/v3/ws?model=universal-3-6-pro |
assemblyai.com |
| AssemblyAI Voice Agent API | (default STT) |
wss://agents.assemblyai.com/v1/ws |
Pricing
| Per hour | $0.45 |
|---|
As published: “per hour of streaming session (same as Universal-3.5 Pro Realtime); Universal-Streaming EN/multi $0.15/hr”.
Source: assemblyai.com, checked 29 September 2026.
Specs
- Input
- Audio and text
- Output
- Text
- Context window
- Not published
- Max output
- Not published
- Open weights
- No
- Licence
- Proprietary
- Released
- 29 September 2026
- Status
- Current
- Type
- Speech and audio
What stands out
What its maker marketed at launch, and what people found later, each with its source.
Promptable streaming STT for voice agents
Prompting + keyterms together, real-time diarization, entity-aware endpointing and native code-switching in 32 languages with auto language detection; 5.13% normalized WER (vs 5.80% for 3.5 Pro Realtime), short-response WER 1.45%; median endpoint latency 537 ms.
Notes
Lineage: Universal-3 Pro Streaming (Mar 2026) -> Universal-3.5 Pro Realtime (2026-06-23) -> 3.6 (2026-09-29). Older streaming ids u3-rt-pro/u3-pro replaced. Voice Agent API ($4.50/hr all-in: STT+LLM+TTS) GA April 2026. AssemblyAI roadmap targets 30+ native languages for the next Universal-3.x in Q4 2026.
Sources: https://www.assemblyai.com/blog/universal-3-6-pro-realtime , https://www.assemblyai.com/llms/models.md , https://www.assemblyai.com/pricing