Voice AI BenchmarksBy

PROVIDERLAST 30 DAYS

official resource

Soniox voice AI models and benchmarks

Soniox lists 3 STT and TTS models in Coval. Fastest dated mean latency over 30 days: STT: STT RT v5 at 45 ms TTFS, with 4.8% WER. TTS: TTS RT v1 at 255 ms TTFA, with 2.4% WER. Last measured .

Soniox builds real-time transcription and synthesis APIs.

Measured models
3
STTTTS
Best STT model#2 / 29
45ms
STT RT v5
Best TTS model#14 / 32
255ms
TTS RT v1

Overview

Soniox builds and serves both its transcription and synthesis endpoints; the TTS line is versioned, with RT v1 and v2 live side by side.

Every model below is measured daily on the same fixed inputs and ranked against the full field, never blended into a company score.

Model lineup

Speech-to-Text
STT RT v5
Text-to-Speech
TTS RT v1, TTS Rt v2

Speech-to-Text

Full STT dashboard

Ranked on Time to Final Segment against 29 measured models.

Time to Final Segmentms · lower is better · Soniox models markedEvery measured STT model on Time to Final Segment, with Soniox's models highlighted.
  1. #1Qwen3 ASR 1.7b39 ms
  2. #2STT RT v545 ms
  3. #3Qwen3 ASR Fast47 ms
  4. #4STT 167 ms
  5. #5Nova 386 ms
  6. #6Nova 287 ms
  7. #7Parakeet TDT 0.6B v397 ms
leaders plus Soniox models · 22 other models in the full table
Word Error Rate% · lower is better · Soniox models markedEvery measured STT model on Word Error Rate, with Soniox's models highlighted.
  1. #1Universal 3.6 Pro2.1%
  2. #2Universal 3.5 Pro2.4%
  3. #3Qwen3 ASR Fast2.6%
  4. #4resonant-12.6%
  5. #5Qwen3 ASR 1.7b2.9%
  6. #6Gemini 3.5 Transcribe Live3.0%
  7. #7Chirp 33.2%
  8. #18STT RT v54.8%
leaders plus Soniox models · 23 other models in the full table
Time to First Tokenms · lower is better · Soniox models markedEvery measured STT model on Time to First Token, with Soniox's models highlighted.
  1. #1Whisper Large v3via Baseten924 ms
  2. #2Qwen3 ASR 1.7b946 ms
  3. #3Universal 3.5 Pro1026 ms
  4. #4Universal 3.6 Pro1071 ms
  5. #5Flux1091 ms
  6. #6Flux Multilingual1165 ms
  7. #7STT 11205 ms
  8. #13STT RT v51518 ms
leaders plus Soniox models · 19 other models in the full table
TTFS vs WER — Soniox vs every measured modelEach point is one measured STT model · Soniox models highlighted · 30-day averagesTime to Final Segment against Word Error Rate for every measured STT model, with Soniox's models highlighted.
Qwen3 ASR 1.7b — 39 ms, 2.9%Qwen3 ASR Fast — 47 ms, 2.6%STT 1 — 67 ms, 7.1%Nova 3 — 86 ms, 5.3%Nova 2 — 87 ms, 6.7%Parakeet TDT 0.6B v3 — 97 ms, 11.1%Flux Multilingual — 98 ms, 7.5%Flux — 99 ms, 5.8%Scribe v2 Realtime — 122 ms, 4.4%Whisper Large v3 via Baseten — 131 ms, 4.5%Universal 3.6 Pro — 135 ms, 2.1%Ink 2 — 149 ms, 3.6%Universal 3.5 Pro — 170 ms, 2.4%Whisper Large v3 via Together AI — 198 ms, 7.4%Pulse — 205 ms, 4.6%Grok STT — 223 ms, 4.1%resonant-1 — 252 ms, 2.6%Default — 261 ms, 8.8%Linden 1 — 274 ms, 3.9%Gemini 3.5 Transcribe Live — 317 ms, 3.0%Daytona STT — 399 ms, 4.9%Voxtral Mini Transcribe Realtime 2602 — 415 ms, 5.4%GPT Realtime Whisper — 599 ms, 4.0%Solaria 1 — 620 ms, 6.1%GPT-4o mini Transcribe — 710 ms, 3.9%Chirp 3 — 768 ms, 3.2%GPT-4o Transcribe — 784 ms, 3.8%Chirp 2 — 909 ms, 3.9%STT RT v5 — 45 ms, 4.8%
Benchmarked models with their Time to Final Segment over the last 30 days.
ModelHostTTFSRank
STT RT v5Soniox45 ms2nd of 29

Text-to-Speech

Full TTS dashboard

Ranked on Time to First Audio against 32 measured models.

Time to First Audioms · lower is better · Soniox models markedEvery measured TTS model on Time to First Audio, with Soniox's models highlighted.
  1. #1vui59 ms
  2. #2Default63 ms
  3. #3Qwen3 TTS Fast68 ms
  4. #4TTS Flash 291 ms
  5. #5Qwen3 TTS 1.7b107 ms
  6. #6Simba 3.0111 ms
  7. #7Palabra TTS120 ms
  8. #14TTS RT v1255 ms
  9. #15TTS Rt v2256 ms
leaders plus Soniox models · 23 other models in the full table
Word Error Rate% · lower is better · Soniox models markedEvery measured TTS model on Word Error Rate, with Soniox's models highlighted.
  1. #1Sonic 3.61.5%
  2. #2S2.1 Pro Free1.5%
  3. #3Simba 3.01.5%
  4. #4S2.1 Pro1.5%
  5. #5Lightning v3.1 Pro1.5%
  6. #6Sonic 3.51.5%
  7. #7Chirp 3 HD1.5%
  8. #28TTS Rt v22.4%
  9. #29TTS RT v12.4%
leaders plus Soniox models · 23 other models in the full table
TTFA vs WER — Soniox vs every measured modelEach point is one measured TTS model · Soniox models highlighted · 30-day averagesTime to First Audio against Word Error Rate for every measured TTS model, with Soniox's models highlighted.
vui — 59 ms, 2.1%Default — 63 ms, 1.9%Qwen3 TTS Fast — 68 ms, 1.8%TTS Flash 2 — 91 ms, 1.7%Qwen3 TTS 1.7b — 107 ms, 1.8%Simba 3.0 — 111 ms, 1.5%Palabra TTS — 120 ms, 2.6%Simba 3.2 — 126 ms, 1.9%drama3-preview — 167 ms, 2.0%TTS 2 — 191 ms, 1.6%Flash v2.5 — 192 ms, 1.8%Eleven v4 Turbo — 201 ms, 1.7%Flux TTS — 205 ms, 1.7%Mist v3 — 287 ms, 2.1%Phantom Z 3.4 conversational — 291 ms, 1.8%Sonic 3.5 — 293 ms, 1.5%Aura 2 — 297 ms, 1.8%Sonic 3.6 — 299 ms, 1.5%Falcon 2 — 300 ms, 1.7%Coda — 332 ms, 9.5%S2.1 Pro — 341 ms, 1.5%Grok TTS — 363 ms, 1.6%S1 — 389 ms, 1.8%Lightning v3.1 Pro — 392 ms, 1.5%Daytona TTS — 486 ms, 1.6%Aura 2 En — 569 ms, 2.1%Chirp 3 HD — 597 ms, 1.5%Qwen3 TTS Flash Realtime — 718 ms, 3.0%S2.1 Pro Free — 850 ms, 1.5%GPT-4o mini TTS — 2585 ms, 1.8%TTS RT v1 — 255 ms, 2.4%TTS Rt v2 — 256 ms, 2.4%
Benchmarked models with their Time to First Audio over the last 30 days.
ModelHostTTFARank
TTS RT v1Soniox255 ms14th of 32
TTS Rt v2Soniox256 ms15th of 32

How fast are Soniox's STT and TTS models?

STT RT v5 measures mean 45 ms time to final segment (2nd of 29) among STT systems. Last measured 2026-10-14. TTS RT v1 measures mean 255 ms time to first audio (14th of 32) among TTS systems. Last measured 2026-10-14. TTS Rt v2 measures mean 256 ms time to first audio (15th of 32) among TTS systems. Last measured 2026-10-14.

How accurate are Soniox's STT and TTS models?

STT RT v5 measures 4.8% word error rate (18th of 31) among STT systems. Last measured 2026-10-14. TTS Rt v2 measures 2.4% word error rate (28th of 32) among TTS systems. Last measured 2026-10-14. TTS RT v1 measures 2.4% word error rate (29th of 32) among TTS systems. Last measured 2026-10-14.

Which Soniox model is fastest?

Its fastest dated STT result is STT RT v5 at mean 45 ms time to final segment (2nd of 29) among STT systems, with 4.8% WER. Last measured 2026-10-14. Its fastest dated TTS result is TTS RT v1 at mean 255 ms time to first audio (14th of 32) among TTS systems, with 2.4% WER. Last measured 2026-10-14.

Limits of this comparison

Coval measures STT RT v5 and the versioned TTS RT v1 and v2 endpoints.

  • The benchmarks do not score Soniox translation, diarization or cloning quality even when those capabilities appear in specifications.

Official resources

Same datasets, prompts and metric definitions for every model, measured by Coval’s open-source runner. Full methodology on the overview.

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