Deepgram Flux English is ahead of GPT-4o Mini Transcribe on final-text delay. The Pipecat Dataset and The Ocular Dataset are too close to call.
Last updated Methodology by Dileep Chagam
Each dot is one model. Bottom-left is best: fewer errors and a faster final transcript.
Deepgram Flux English is the better pick over GPT-4o Mini Transcribe on every measure that separates them: quick turn-taking once the caller stops (522ms sooner). For accuracy on clean, scripted audio and accuracy on real phone conversations, the gap is inside the margin of error, so neither is ahead.
Too close to call: inside the margin of error
Too close to call: inside the margin of error
Not comparable
Deepgram Flux English, 522ms sooner
Lower is better on every metric. The small figure is each model's place in the whole field. What each metric measures.
Deepgram Flux English shows first text after 1.51s and final text after 141ms, and GPT-4o Mini Transcribe shows first text after 40.84s and final text after 1.53s, on a bad turn (P95) across the same streamed turns.
| Measure | Model | P50 | P90 | P95 |
|---|---|---|---|---|
| Time to first text | Deepgram Flux English | 791ms | 1.23s | 1.51s |
| GPT-4o Mini Transcribe | No text until the speaker stops | |||
| Final-text delay | Deepgram Flux English | 108ms | 132ms | 141ms |
| GPT-4o Mini Transcribe | 630ms | 1.34s | 1.53s | |
Place among the 17 models on each metric. Lower is better on all four.
| Metric | Flux English | 4o Mini Transcribe |
|---|---|---|
| Pipecat Dataset WER | 3.90%15th of 17 | 3.35%11th of 17 |
| Ocular Dataset WER | 4.18%8th of 17 | 4.45%12th of 17 |
| Time to first text | 791ms3rd of 15 | Not comparable |
| Final-text delay | 108ms5th of 17 | 630ms16th of 17 |
| Model | Pipecat clips | Ocular recordings | Turns timed | Failed |
|---|---|---|---|---|
| Deepgram Flux English | 999 | 8 | 199 | 7 |
| GPT-4o Mini Transcribe | 1,000 | 8 | 206 | 0 |
Only clips with usable text count, so the two totals can differ. How WER is scored.
Both providers, every model: Deepgram vs OpenAI
Deepgram Flux English and GPT-4o Mini Transcribe are too close to call on accuracy. On the 1,000 public Pipecat clips, Deepgram Flux English scores 3.90% and GPT-4o Mini Transcribe 3.35%, with likely ranges of 3.53 to 4.29% and 3.08 to 3.65%. The ranges overlap, so the difference is too close to call. On the eight licensed Ocular recordings, Deepgram Flux English scores 4.18% and GPT-4o Mini Transcribe 4.45%, with likely ranges of 3.08 to 5.23% and 3.22 to 5.55%. 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. Deepgram Flux English finishes the transcript 522ms sooner. Deepgram Flux English has the final transcript 108ms after the speaker stops and GPT-4o Mini Transcribe 630ms, at the median. Both are measured on the same 206 streamed turns.
Deepgram Flux English finishes the transcript 522ms 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.
Only Deepgram Flux English. GPT-4o Mini Transcribe returns no text until the speaker stops, which matters if your agent reacts to partial transcripts.