AssemblyAI Universal 3.5 Pro vs Inworld STT-1
Accuracy and speed
Left gets fewer words wrong. Lower has the final text ready sooner.
- Universal 3.5 Pro1.93% · 180ms
- STT-12.72% · 41ms
AssemblyAI Universal 3.5 Pro is ahead on both datasets together and time to first text, and Inworld STT-1 on final-text delay. 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 Inworld STT-1.
Last updated Methodology by Dileep Chagam
Who is better at what
- Overall WER2.72%5.44%
- Pipecat Dataset WER1.93%2.72%
- Ocular Dataset WER4.23%10.60%
- Time to first text489ms1.06s
- Final-text delay180ms41ms
Lower is better on every measure. Too close to call means the likely ranges overlap.
Universal 3.5 Pro vs STT-1 FAQ
Which is more accurate, AssemblyAI Universal 3.5 Pro or Inworld STT-1?
AssemblyAI Universal 3.5 Pro is more accurate on the public clips. On the 1,000 public Pipecat clips, AssemblyAI Universal 3.5 Pro scores 2.72% and Inworld STT-1 5.44%, so AssemblyAI Universal 3.5 Pro makes fewer errors by 2.72 points. On the eight licensed Ocular recordings, AssemblyAI Universal 3.5 Pro scores 1.93% and Inworld STT-1 2.72%, with likely ranges of 1.69 to 2.18% and 1.67 to 4.68%. The ranges overlap, so the difference is too close to call. Word error rate counts incorrect, missing, and extra words, so lower is better.
AssemblyAI Universal 3.5 Pro is more accurate on the public clips. On the 1,000 public Pipecat clips, AssemblyAI Universal 3.5 Pro scores 2.72% and Inworld STT-1 5.44%, so AssemblyAI Universal 3.5 Pro makes fewer errors by 2.72 points. On the eight licensed Ocular recordings, AssemblyAI Universal 3.5 Pro scores 1.93% and Inworld STT-1 2.72%, with likely ranges of 1.69 to 2.18% and 1.67 to 4.68%. 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 574ms sooner. AssemblyAI Universal 3.5 Pro has the final transcript 489ms after the speaker stops and Inworld STT-1 1.06s, at the median. Both are measured on the same 206 streamed turns.
AssemblyAI Universal 3.5 Pro finishes the transcript 574ms 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 Inworld STT-1 after 10.60%, at the median.
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