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DeepgramGradium

Deepgram Flux English vs Gradium

Deepgram Flux English is ahead of Gradium on the Pipecat Dataset, time to first text and final-text delay. The Ocular Dataset is too close to call.

Last updated Methodology by Dileep Chagam

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Accuracy vs speed

Each dot is one model. Bottom-left is best: fewer errors and a faster final transcript.

Top half on bothBest picks
Final-text delay P50 (ms)
Pipecat Dataset WER (%)
Shaded box: top half on both measures. Dotted line: no other model is both more accurate and faster.
Verdict

Which to pick

Deepgram Flux English is the better pick over Gradium on every measure that separates them: accuracy on clean, scripted audio (2.57 points lower), showing words while the caller is still talking (914ms sooner) and quick turn-taking once the caller stops (104ms sooner). For accuracy on real phone conversations, the gap is inside the margin of error, so neither is ahead.

Head to head

The four metrics, side by side

Pipecat Dataset WER
Deepgram Flux English
3.90%15th
Gradium
6.48%17th

Deepgram Flux English, 2.57 points lower

Ocular Dataset WER
Deepgram Flux English
4.18%8th
Gradium
4.45%12th

Too close to call: inside the margin of error

Time to first text
Deepgram Flux English
791ms3rd
Gradium
1.71s12th

Deepgram Flux English, 914ms sooner

Final-text delay
Deepgram Flux English
108ms5th
Gradium
212ms11th

Deepgram Flux English, 104ms sooner

Lower is better on every metric. The small figure is each model's place in the whole field. What each metric measures.

WER · Word error rate
Share of words the model got wrong: replaced, missing or added. Lower is better.
Pipecat Dataset
1,000 short public clips from Pipecat's STT benchmark dataset.
Ocular Dataset
8 recordings from 4 real phone conversations, licensed from Ocular.
TTFT · Time to first text
How long after the audio starts streaming until the first words appear.
TTFS · Final-text delay
How long after the caller stops until the full transcript arrives. A voice agent waits for this before it replies.
Latency

First text and final text, at three percentiles

Deepgram Flux English shows first text after 1.51s and final text after 141ms, and Gradium shows first text after 7.32s and final text after 280ms, on a bad turn (P95) across the same streamed turns.

MeasureModelP50P90P95
Time to first textDeepgram Flux English791ms1.23s1.51s
Gradium1.71s4.05s7.32s
Final-text delayDeepgram Flux English108ms132ms141ms
Gradium212ms266ms280ms
P50 / P90 / P95 · Typical, slow and slowest turns
Half of turns are faster than P50. Only 1 in 10 is slower than P90, and 1 in 20 slower than P95.
Ranking

How each ranks among all 17 models

Place among the 17 models on each metric. Lower is better on all four.

MetricFlux EnglishGradium
Pipecat Dataset WER3.90%15th of 176.48%17th of 17
Ocular Dataset WER4.18%8th of 174.45%12th of 17
Time to first text791ms3rd of 151.71s12th of 15
Final-text delay108ms5th of 17212ms11th of 17
Coverage

How much audio each model was tested on

ModelPipecat clipsOcular recordingsTurns timedFailed
Deepgram Flux English99981997
Gradium1,00081980

Only clips with usable text count, so the two totals can differ. How WER is scored.

Questions

Frequently asked questions

Which is more accurate, Deepgram Flux English or Gradium?

Deepgram Flux English is more accurate on the public clips. On the 1,000 public Pipecat clips, Deepgram Flux English scores 3.90% and Gradium 6.48%, so Deepgram Flux English makes fewer errors by 2.57 points. On the eight licensed Ocular recordings, Deepgram Flux English scores 4.18% and Gradium 4.45%, with likely ranges of 3.08 to 5.23% and 3.17 to 5.90%. The ranges overlap, so the difference is too close to call. Word error rate counts incorrect, missing, and extra words, so lower is better.

Is Deepgram Flux English faster than Gradium?

Yes. Deepgram Flux English finishes the transcript 104ms sooner. Deepgram Flux English has the final transcript 108ms after the speaker stops and Gradium 212ms, at the median. Both are measured on the same 206 streamed turns.

Is Deepgram Flux English or Gradium better for voice agents?

Deepgram Flux English finishes the transcript 104ms 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.

Do Deepgram Flux English and Gradium stream text while the speaker is talking?

Yes, both return partial text before the speaker stops. Deepgram Flux English shows first text after 791ms and Gradium after 1.71s, at the median, so Deepgram Flux English is 914ms sooner.