AssemblyAI Universal 3.5 Pro vs GPT Realtime Whisper
Accuracy and speed
Left gets fewer words wrong. Lower has the final text ready sooner.
- Universal 3.5 Pro1.93% · 180ms
- Realtime Whisper2.16% · 543ms
AssemblyAI Universal 3.5 Pro is ahead on time to first text and final-text delay, and GPT Realtime Whisper on both datasets together. The Pipecat Dataset and The Ocular Dataset are too close to call. AssemblyAI Universal 3.5 Pro has a newer release: AssemblyAI Universal 3.6 Pro vs GPT Realtime Whisper.
Last updated Methodology by Dileep Chagam
Who is better at what
- Overall WER2.72%2.63%
- Pipecat Dataset WER1.93%2.16%
- Ocular Dataset WER4.23%3.53%
- Time to first text489ms1.38s
- Final-text delay180ms543ms
Lower is better on every measure. Too close to call means the likely ranges overlap.
Universal 3.5 Pro vs Realtime Whisper FAQ
Which is more accurate, AssemblyAI Universal 3.5 Pro or GPT Realtime Whisper?
GPT Realtime Whisper is more accurate on the public clips. On the 1,000 public Pipecat clips, AssemblyAI Universal 3.5 Pro scores 2.72% and GPT Realtime Whisper 2.63%, so GPT Realtime Whisper makes fewer errors by 0.09 points. On the eight licensed Ocular recordings, AssemblyAI Universal 3.5 Pro scores 1.93% and GPT Realtime Whisper 2.16%, with likely ranges of 1.69 to 2.18% and 1.92 to 2.41%. The ranges overlap, so the difference is too close to call. Word error rate counts incorrect, missing, and extra words, so lower is better.
GPT Realtime Whisper is more accurate on the public clips. On the 1,000 public Pipecat clips, AssemblyAI Universal 3.5 Pro scores 2.72% and GPT Realtime Whisper 2.63%, so GPT Realtime Whisper makes fewer errors by 0.09 points. On the eight licensed Ocular recordings, AssemblyAI Universal 3.5 Pro scores 1.93% and GPT Realtime Whisper 2.16%, with likely ranges of 1.69 to 2.18% and 1.92 to 2.41%. The ranges overlap, so the difference is too close to call. Word error rate counts incorrect, missing, and extra words, so lower is better.
Yes. AssemblyAI Universal 3.5 Pro finishes the transcript 890ms sooner. AssemblyAI Universal 3.5 Pro has the final transcript 489ms after the speaker stops and GPT Realtime Whisper 1.38s, at the median. Both are measured on the same 206 streamed turns.
AssemblyAI Universal 3.5 Pro finishes the transcript 890ms sooner, and the two are too close to call on real conversations. A voice agent cannot reply until the final transcript arrives, and the Ocular recordings are real conversations.
Yes, both return partial text before the speaker stops. AssemblyAI Universal 3.5 Pro shows first text after 4.23% and GPT Realtime Whisper after 3.53%, at the median.
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