Converse-STT
Deepgram

Deepgram Flux English

Deepgram Flux English is 3rd of 15 on time to first text and 15th of 17 on the Pipecat Dataset.

Last updated Methodology by Dileep Chagam

3.90%
Pipecat WER · 15th
4.18%
Ocular WER · 8th
791ms
First text · 3rd
108ms
Final text · 5th

Likely range, with 95% confidence: Pipecat WER 3.53 to 4.29%, Ocular WER 3.08 to 5.23%.

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.
Ranking

Deepgram Flux English against every other model

Open on the metric Deepgram Flux English places highest on, with the other three a tab away. Lower is better on all of them, so the order runs best first.

Time to first text, measured from the first audio packet. Lower is better.

#ModelFirst textturns
1AssemblyAI Universal 3.6 Pro485ms206
2AssemblyAI Universal 3.5 Pro489ms205
3Deepgram Flux English791ms199
4Deepgram Flux Multilingual793ms175
5Smallest Pulse1057ms206
6Inworld STT-11063ms206
7Deepgram Nova-31064ms203
8Speechmatics Linden1190ms194
9Soniox STT-RT v51195ms200
10GPT Realtime Whisper1379ms206
11Cartesia Ink 21511ms198
12Gradium1705ms198
13Reson82400ms201
14Google Chirp 34480ms206
15Google Chirp 24497ms205

Not ranked: GPT-4o Mini Transcribe and GPT-4o Transcribe return no text until the speaker stops, so first-text time is not comparable.

Median across the same 206 Ocular Dataset turns. Providers finalize differently, so compare models with similar finalization contracts before treating small gaps as meaningful.

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.
Likely range · 95% range
Where the model's true score probably falls, given how much audio was tested. Overlapping ranges are too close to call.
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

Measured on the same 206 streamed Ocular Dataset turns as every other model. P90 and P95 say what a caller meets on a bad turn, which a median hides.

MeasureP50P90P95
Time to first text791ms1.23s1.51s
Final-text delay108ms132ms141ms
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.
Against the field

Deepgram Flux English on the other two views

The same charts the benchmark page carries, with Deepgram Flux English ringed. Consistency across the two datasets is one reading; how fast a model starts against how fast it commits is the other.

Public clips vs real calls

Each dot is one model. Bottom-left is best on both datasets.

Top half on both
Ocular Dataset WER (%)
Pipecat Dataset WER (%)
Diagonal line: same error rate on both. Above it, a model does worse on real calls. Shaded box: top half on both measures.

First words vs final transcript

Each dot is one model. Bottom-left is fastest at both.

Top half on both
Final-text delay P50 (ms)
Time to first text P50 (ms)
Shaded box: top half on both measures.
Coverage

How much audio it was tested on

999
Pipecat clips scored
8
Ocular recordings scored
199
turns timed
7
requests that failed

A clip counts only where the model returned usable text, so counts differ between models. Word error rate is measured the same way throughout: incorrect, missing, and extra words against the reference transcript.

Questions

Frequently asked questions

Where does Deepgram Flux English place in the benchmark?

Deepgram Flux English places highest on time to first text, 3rd of 15 at 791ms. Its weakest placing is the Pipecat Dataset, 15th of 17 at 3.90%.

How accurate is Deepgram Flux English?

Deepgram Flux English transcribes the 1,000 public Pipecat clips at 3.90% word error rate and the eight licensed Ocular recordings at 4.18%. Word error rate counts incorrect, missing, and extra words against the reference transcript, so lower is better.

How fast is Deepgram Flux English in a live conversation?

First text arrives after 791ms at the median, and the transcript is final 108ms after the speaker stops. Both are measured on the same 206 streamed turns as every other model, and the page shows P90 and P95 as well, which is what a caller meets on a bad turn.

How was Deepgram Flux English measured?

Every model runs the same two datasets under the same conditions: 1,000 public clips from Pipecat's STT benchmark dataset for accuracy at scale, and eight licensed conversation recordings from Ocular for real speech. Latency comes from 206 streamed turns, using each provider's own supported finalization contract. Deepgram Flux English returned usable text for 999 of the public clips.