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Nova-3 vs GPT-4o Transcribe Diarize

2 models compared on the same benchmark — accuracy, latency, price, language coverage and capabilities. GPT-4o Transcribe Diarize leads on raw accuracy; GPT-4o Transcribe Diarize is fastest; Nova-3 covers the most languages; GPT-4o Transcribe Diarize is cheapest.

Open both in playground

Verdict · who wins what

Most accurate

GPT-4o Transcribe Diarize

14.6% WER

OpenAI

Fastest

GPT-4o Transcribe Diarize

0.2× realtime

OpenAI

Most languages

Nova-3

47 languages

Deepgram

Cheapest

GPT-4o Transcribe Diarize

$0.0060/min

OpenAI

Comparing

2 models · same benchmark

1

Batch & Realtime

Nova-3

Deepgram

$0.0077/min
#29 · 71.1

Deepgram's flagship model — 53% lower WER vs competitors, code-switching support

Use This ModelDetails →

2

Batch

GPT-4o Transcribe Diarize

OpenAI

$0.0060/min
#12 · 50.7

GPT-4o transcription with built-in speaker diarization

Use This ModelDetails →

Overview

30-day benchmark average

Overall score

0–100

71.1

50.7

Accuracy rank

of 35

#29

#12

Word error rate

WER

21.0%

14.6%

Character error rate

CER

11.5%

10.0%

Match error rate

MER

20.0%

13.5%

Word info lost

WIL

25.8%

19.9%

Languages

47

12

Cost vs. accuracy

overall WER vs price

GPT-4o Transcribe Diarize

Nova-3

field · 33 models

lower-left is better

Accuracy by category

WER · lower is better

code_switching

63.0%
25.5%

conversational

12.2%
12.2%

finance

9.5%
6.3%

Accuracy by accent

WER · English

african

26.2%
27.7%

australian

15.4%
29.2%

indian

27.0%

Speed & latency

p50 → p99

Processing speed

× realtime

0.1×

0.2×

Latency p50

1.3s

17.2s

Latency p90

1.8s

18.1s

Realtime / streaming

Streaming benchmark averages

Realtime rank

of 17

#3

—

Realtime score

0–100

78.2

—

Time to first word

973ms

—

Reliability

Rolling 30 days

Uptime

100.00%

100.00%

Error rate

0.00%

0.00%

Pricing

billed per second

Rate

per minute

$0.0077

$0.0060

Billing granularity

per 1s

per 1s

1 hour of audio

$0.46

$0.36

100 hours

$46.08

Capabilities

Feature support

Speaker diarization

Yes

Yes

Word-level timestamps

Yes

No

Code-switching

Yes

Coverage & deployment

Languages · formats · regions

Languages

47

12

Mode

Batch & Realtime

Batch

Region

United States

United States

Audio formats

general

23.4%
14.5%

legal

3.8%
2.3%

medical

9.5%
1.9%

noisy

21.8%
32.5%

technical

2.8%
4.6%
36.5%

uk

6.0%
13.4%

us

11.3%
18.9%

Latency p99

1.8s

18.1s

Final drain

181ms

—

Real-time factor

1.01×

—

Flicker

9.6%

—

Cadence

0.8/s

—

$36.00

1,000 hours

$460.80

$360.00

No

Auto-detect language

Yes

Yes

Live / streaming

Yes

No

Custom vocabulary

Yes

No

mp3
wav
flac
m4a
ogg
webm
mp3
wav
flac
m4a
ogg
webm

Max file size

2 GB

25 MB

Max duration

No limit

No limit

Compliance

HIPAA
SOC2
GDPR
SOC2
GDPR

Frequently asked questions

Is Nova-3 or GPT-4o Transcribe Diarize more accurate?

GPT-4o Transcribe Diarize is more accurate, with a 14.6% word error rate versus 21.0% for Nova-3, on our standardized benchmark.

Which is cheaper, Nova-3 or GPT-4o Transcribe Diarize?

GPT-4o Transcribe Diarize is cheaper at $0.0060/min versus $0.0077/min for Nova-3.

Should you choose Nova-3 or GPT-4o Transcribe Diarize?

Choose Nova-3 for language coverage; choose GPT-4o Transcribe Diarize for accuracy, speed, and lower cost.