GPT Realtime Whisper vs Speechmatics Linden
Accuracy and speed
Left gets fewer words wrong. Lower has the final text ready sooner.
- Realtime Whisper2.16% · 543ms
- Linden2.46% · 147ms
Speechmatics Linden 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.
Last updated Methodology by Dileep Chagam
Who is better at what
- Overall WER2.63%2.97%
- Pipecat Dataset WER2.16%2.46%
- Ocular Dataset WER3.53%3.93%
- Time to first text1.38s1.19s
- Final-text delay543ms147ms
Lower is better on every measure. Too close to call means the likely ranges overlap. Our guide covers testing OpenAI Realtime API voice agents.
Realtime Whisper vs Linden FAQ
Which is more accurate, GPT Realtime Whisper or Speechmatics Linden?
GPT Realtime Whisper is more accurate on the public clips. On the 1,000 public Pipecat clips, GPT Realtime Whisper scores 2.63% and Speechmatics Linden 2.97%, so GPT Realtime Whisper makes fewer errors by 0.34 points. On the eight licensed Ocular recordings, GPT Realtime Whisper scores 2.16% and Speechmatics Linden 2.46%, with likely ranges of 1.92 to 2.41% and 2.19 to 2.73%. 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, GPT Realtime Whisper scores 2.63% and Speechmatics Linden 2.97%, so GPT Realtime Whisper makes fewer errors by 0.34 points. On the eight licensed Ocular recordings, GPT Realtime Whisper scores 2.16% and Speechmatics Linden 2.46%, with likely ranges of 1.92 to 2.41% and 2.19 to 2.73%. The ranges overlap, so the difference is too close to call. Word error rate counts incorrect, missing, and extra words, so lower is better.
No. Speechmatics Linden finishes the transcript 189ms sooner. GPT Realtime Whisper has the final transcript 1.38s after the speaker stops and Speechmatics Linden 1.19s, at the median. Both are measured on the same 206 streamed turns.
Speechmatics Linden finishes the transcript 189ms 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. GPT Realtime Whisper shows first text after 3.53% and Speechmatics Linden after 3.93%, at the median.
Test your voice agent the same way.
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