2 models compared on the same benchmark — accuracy, latency, price, language coverage and capabilities. Soniox STT (Async) leads on raw accuracy; Universal-3.5 Pro is fastest; Soniox STT (Async) covers the most languages; Soniox STT (Async) is cheapest.
Verdict · who wins what
Most accurate
Soniox STT (Async)
8.7% WER
Soniox
Fastest
Universal-3.5 Pro
0.2× realtime
AssemblyAI
Most languages
Soniox STT (Async)
25 languages
Soniox
Cheapest
Soniox STT (Async)
$0.0017/min
Soniox
Comparing
2 models · same benchmark
1
Universal-3.5 Pro
AssemblyAI
AssemblyAI's most powerful speech language model — up to 1000 keyterm phrases
2
Soniox STT (Async)
Soniox
Soniox async batch transcription — one multilingual model across 60+ languages with speaker diarization, per-word timestamps, and automatic language identification, at a low flat token-based rate.
Soniox STT (Async)
Universal-3.5 Pro
field · 33 models
lower-left is better
general
legal
medical
noisy
technical
uk
us
Latency p99
5.8s
6.2s
$10.08
1,000 hours
$208.80
$100.80
No
Auto-detect language
Yes
Yes
Live / streaming
No
No
Custom vocabulary
Yes
No
Max file size
5 GB
No limit
Max duration
10 h
5 h
Compliance
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Is Universal-3.5 Pro or Soniox STT (Async) more accurate?
Soniox STT (Async) is more accurate, with a 8.7% word error rate versus 17.4% for Universal-3.5 Pro, on our standardized benchmark.
Which is cheaper, Universal-3.5 Pro or Soniox STT (Async)?
Soniox STT (Async) is cheaper at $0.0017/min versus $0.0035/min for Universal-3.5 Pro.
Should you choose Universal-3.5 Pro or Soniox STT (Async)?
Choose Universal-3.5 Pro for speed; choose Soniox STT (Async) for accuracy, lower cost, and language coverage.
