Voice AI BenchmarksBy

SPEECHIFYTEXT-TO-SPEECH45,566 SAMPLES / 30 DAYSLAST RUN SEP 15, 2026, 07:00 UTC

official resource

Simba 3.0 text-to-speech benchmarks

Simba 3.0, hosted by Speechify, measures mean 471 ms time to first audio (23rd of 28) and 5.2% word error rate (16th of 28) among TTS systems. Results cover the last 30 days. Coval benchmarks hosted endpoints daily using a consistent evaluation methodology. Last measured .

Simba 3.0 is a Speechify synthesis model and the predecessor to Simba 3.2.

Time to First Audio#23 / 28
471ms
TTFA Network Roundtrip#24 / 28
392ms
TTFA Leading Silence#16 / 28
80ms
Word Error Rate#16 / 28
5.2%

Overview

Simba 3.0 streams voices with multilingual, cloning and expressive controls.

Simba 3.0 is tested every day on a fixed set of text prompts, measuring how quickly audible speech starts and how intelligible the result is.

Technical specifications

Made by
Speechify
Hosted by
Speechify
Source
Official API
Licensing
Proprietary
Deployment
Cloud
Region
US
Features
Emotion control, Multilingual, Voice cloning

How Simba 3.0 ranks

Full TTS dashboard
Time to First Audio — every measured TTS modelMilliseconds · lower is better · 30-day averageEvery TTS model ranked on Time to First Audio, with Simba 3.0 highlighted.
  1. #1vui66 ms
  2. #2Qwen3 TTS Fast71 ms
  3. #3TTS Flash 291 ms
  4. #4Qwen3 TTS 1.7b106 ms
  5. #5Palabra TTS v1115 ms
  6. #6TTS 2181 ms
  7. #7Flash v2.5194 ms
  8. #8Default235 ms
  9. #9TTS Rt v2245 ms
  10. #10TTS RT v1245 ms
  11. #11Mist v3258 ms
  12. #12Sonic 3.5276 ms
  13. #13Phantom Z 3.4 conversational286 ms
  14. #14Aura 2308 ms
  15. #15Coda312 ms
  16. #16S2.1 Pro335 ms
  17. #17Eleven v3 Conversational348 ms
  18. #18Lightning v3.1 Pro362 ms
  19. #19S1379 ms
  20. #20Grok TTS397 ms
  21. #21Sonic 3.6423 ms
  22. #22Simba 3.2452 ms
  23. #23Simba 3.0471 ms
Show all 28 models
  1. #24Chirp 3 HD535 ms
  2. #25Falcon 2545 ms
  3. #26Qwen3 TTS Flash Realtime754 ms
  4. #27S2.1 Pro Free965 ms
  5. #28GPT-4o mini TTS1013 ms
median of all models · 310 ms
TTS models over the last 30 days, ranked on Time to First Audio.
#ModelHostTTFAWERSamples
1vuiFluxions66 ms9,450
2Qwen3 TTS FastNari71 ms2,190
3TTS Flash 2Inworld AI91 ms11,401
4Qwen3 TTS 1.7bBaseten106 ms420
5Palabra TTS v1Palabra115 ms11,385
6TTS 2Inworld AI181 ms11,401
7Flash v2.5ElevenLabs194 ms9,118
8DefaultGradium235 ms9,127
9TTS Rt v2Soniox245 ms11,232
10TTS RT v1Soniox245 ms11,234
11Mist v3Rime258 ms11,387
12Sonic 3.5Cartesia276 ms11,400
13Phantom Z 3.4 conversationalDeepdub286 ms11,396
14Aura 2Deepgram308 ms11,386
15CodaRime312 ms11,392
16S2.1 ProFish Audio335 ms11,400
17Eleven v3 ConversationalElevenLabs348 ms11,389
18Lightning v3.1 ProSmallest362 ms11,401
19S1Fish Audio379 ms11,393
20Grok TTSxAI397 ms11,386
21Sonic 3.6Cartesia423 ms8,210
22Simba 3.2Speechify452 ms11,393
23Simba 3.0Speechify471 ms11,396
24Chirp 3 HDGoogle535 ms11,400
25Falcon 2Murf545 ms11,397
26Qwen3 TTS Flash RealtimeAlibaba754 ms11,226
27S2.1 Pro FreeFish Audio965 ms11,366
28GPT-4o mini TTSOpenAI1013 ms11,370
Under-sampled models are excluded; tied models share a place. Dotted WER values split into substitutions, deletions and insertions on hover or tap.

Highest relative placement: 16th of 28 on Word Error Rate.

Latency vs accuracy

TTFA vs WEREach point is one measured model · Simba 3.0 highlighted · 30-day averagesTime to First Audio against Word Error Rate for every measured TTS model, with Simba 3.0 highlighted.
vui — 66 ms, 5.5%Qwen3 TTS Fast — 71 ms, 4.2%TTS Flash 2 — 91 ms, 5.4%Qwen3 TTS 1.7b — 106 ms, 5.5%Palabra TTS v1 — 115 ms, 5.8%TTS 2 — 181 ms, 4.6%Flash v2.5 — 194 ms, 6.7%Default — 235 ms, 5.3%TTS Rt v2 — 245 ms, 4.2%TTS RT v1 — 245 ms, 3.9%Mist v3 — 258 ms, 5.6%Sonic 3.5 — 276 ms, 5.9%Phantom Z 3.4 conversational — 286 ms, 6.0%Aura 2 — 308 ms, 5.2%Coda — 312 ms, 5.0%S2.1 Pro — 335 ms, 4.8%Eleven v3 Conversational — 348 ms, 4.4%Lightning v3.1 Pro — 362 ms, 4.4%S1 — 379 ms, 4.9%Grok TTS — 397 ms, 4.9%Sonic 3.6 — 423 ms, 5.3%Simba 3.2 — 452 ms, 4.4%Chirp 3 HD — 535 ms, 5.2%Falcon 2 — 545 ms, 5.2%Qwen3 TTS Flash Realtime — 754 ms, 8.9%S2.1 Pro Free — 965 ms, 4.7%GPT-4o mini TTS — 1013 ms, 4.8%Simba 3.0 — 471 ms, 5.2%

Where the errors come from

WER compositionSimba 3.0's Word Error Rate split by error type · 30-day averageSimba 3.0's WER split into substitutions, deletions and insertions.
  • Simba 3.05.2%
SubstitutionsDeletionsInsertions

Averages and tail latency

Averages hide slow outliers — these are the distributions behind each figure.

Simba 3.0 latency distributionMilliseconds · shared axis across metrics · last 30 daysSimba 3.0's latency percentiles per metric: p25–p75 band, p50 tick, whisker to p99.
  • Time to First Audiop50 430 ms · p99 1012 ms
  • TTFA Network Roundtripp50 347 ms · p99 925 ms
  • TTFA Leading Silencep50 79 ms · p99 196 ms
band p25–p75 · tick p50 · whisker to p99 with p90 and p95 stops
Average and percentile values per metric, with the number of samples behind each row.
MetricAveragep25p50p75p90p95p99Samples
Time to First Audio471 ms398 ms430 ms474 ms544 ms627 ms1012 ms11,396
TTFA Network Roundtrip392 ms333 ms347 ms377 ms442 ms546 ms925 ms11,396
TTFA Leading Silence80 ms47 ms79 ms95 ms129 ms157 ms196 ms11,396
Word Error Rate5.2%0.0%0.0%7.7%18.8%24.0%36.0%11,378

Last 30 days

Daily medians from the same measurement runs · gaps are days without qualifying runs.

Time to First Audio — daily p50Line p50 · band p25–p75 · UTC daysSimba 3.0's daily median Time to First Audio over the last 30 days.
Simba 3.0 · Sep 1: 450 msSimba 3.0 · Sep 2: 427 msSimba 3.0 · Sep 3: 425 msSimba 3.0 · Sep 4: 416 msSimba 3.0 · Sep 5: 422 msSimba 3.0 · Sep 6: 428 msSimba 3.0 · Sep 7: 427 msSimba 3.0 · Sep 8: 454 msSimba 3.0 · Sep 9: 434 msSimba 3.0 · Sep 10: 426 msSimba 3.0 · Sep 11: 435 msSimba 3.0 · Sep 12: 434 msSimba 3.0 · Sep 13: 445 msSimba 3.0 · Sep 14: 437 msSimba 3.0 · Sep 15: 461 ms
Word Error Rate — daily averageDaily average · UTC daysSimba 3.0's daily Word Error Rate over the last 30 days.
Simba 3.0 · Sep 1: 2.6%Simba 3.0 · Sep 2: 4.8%Simba 3.0 · Sep 3: 4.7%Simba 3.0 · Sep 4: 5.4%Simba 3.0 · Sep 5: 5.7%Simba 3.0 · Sep 6: 6.0%Simba 3.0 · Sep 7: 5.2%Simba 3.0 · Sep 8: 5.4%Simba 3.0 · Sep 9: 6.1%Simba 3.0 · Sep 10: 5.6%Simba 3.0 · Sep 11: 5.0%Simba 3.0 · Sep 12: 5.0%Simba 3.0 · Sep 13: 5.0%Simba 3.0 · Sep 14: 5.6%Simba 3.0 · Sep 15: 4.2%

Time to First Audio by dataset

Simba 3.0 by test conditionMilliseconds · lower is better · best condition firstSimba 3.0's Time to First Audio on each benchmark dataset.
  1. Text prompts471 ms
Time to First Audio per dataset, with the number of samples behind each figure.
DatasetTTFASamples
Text prompts471 ms11,396

Strongest condition: Text prompts at 471 ms · weakest: Text prompts at 471 ms.

How fast is Simba 3.0?

On Speechify, Simba 3.0 measures mean 471 ms time to first audio (23rd of 28). Last measured 2026-09-15.

How accurate is Simba 3.0?

On Speechify, Simba 3.0 measures 5.2% word error rate (16th of 28). Last measured 2026-09-15.

Who hosts Simba 3.0?

Simba 3.0 is created by Speechify and served by Speechify. Coval measures each hosted endpoint separately.

Limits of this comparison

Both versions receive the same prompts for a direct comparison.

  • The benchmark does not rate naturalness, clone fidelity or every Speechify voice.

Official sources

Results are re-measured daily using fixed datasets and reported over a rolling 30-day window. 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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