Voice AI BenchmarksBy

ELEVENLABSTEXT-TO-SPEECH30,296 SAMPLES / 30 DAYSLAST RUN AUG 28, 2026, 21:30 UTC

official resource

Flash v2.5 text-to-speech benchmarks

Eleven Flash v2.5 is ElevenLabs' latency-oriented multilingual synthesis model.

Time to First Audio#20 / 30
455ms
TTFA Network Roundtrip#24 / 28
392ms
TTFA Leading Silence#6 / 28
40ms
Word Error Rate#27 / 30
6.7%

Overview

Flash v2.5 is built for real-time use with voice cloning; network and leading-silence timing components are reported separately where available.

Flash v2.5 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
ElevenLabs
Hosted by
ElevenLabs
Source
Official API
Licensing
Proprietary
Deployment
Cloud
Region
US
Features
Multilingual, Voice cloning

How Flash v2.5 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 Flash v2.5 highlighted.
  1. #1Palabra TTS v1116 ms
  2. #2vui124 ms
  3. #3TTS Flash 2128 ms
  4. #4TTS 2176 ms
  5. #5Blizzard235 ms
  6. #6Neural236 ms
  7. #7Mist v3256 ms
  8. #8TTS Rt v2262 ms
  9. #9Sonic 3.5274 ms
  10. #10TTS RT v1275 ms
  11. #11Dragon HD Latest310 ms
  12. #12Coda313 ms
  13. #13Aura 2328 ms
  14. #14S2.1 Pro374 ms
  15. #15Default384 ms
  16. #16Speech 2.8 Turbo411 ms
  17. #17Eleven v3 Conversational412 ms
  18. #18Grok TTS420 ms
  19. #19S1434 ms
  20. #20Flash v2.5455 ms
Show all 30 models
  1. #21Speech 2.8 HD460 ms
  2. #22Sonic 3.6466 ms
  3. #23Simba 3.2484 ms
  4. #24Chirp 3 HD512 ms
  5. #25Simba 3.0526 ms
  6. #26Falcon 2549 ms
  7. #27Lightning v3.1 Pro586 ms
  8. #28Qwen3 TTS Flash Realtime645 ms
  9. #29S2.1 Pro Free806 ms
  10. #30GPT-4o mini TTS1075 ms
median of all models · 397 ms
TTS models over the last 30 days, ranked on Time to First Audio.
#ModelHostTTFAWERSamples
1Palabra TTS v1Palabra116 ms5.9%14,396
2vuiFluxions124 ms8,624
3TTS Flash 2Inworld AI128 ms8,719
4TTS 2Inworld AI176 ms4.8%14,529
5BlizzardLmnt235 ms7.4%14,117
6NeuralAzure236 ms4.3%3,350
7Mist v3Rime256 ms6.3%14,524
8TTS Rt v2Soniox262 ms8,849
9Sonic 3.5Cartesia274 ms6.1%14,513
10TTS RT v1Soniox275 ms3.7%14,528
11Dragon HD LatestAzure310 ms5.1%3,350
12CodaRime313 ms5.2%14,523
13Aura 2Deepgram328 ms5.3%14,501
14S2.1 ProFish Audio374 ms10,222
15DefaultGradium384 ms4.6%14,002
16Speech 2.8 TurboMiniMax411 ms4.8%1,997
17Eleven v3 ConversationalElevenLabs412 ms6,750
18Grok TTSxAI420 ms4.7%14,524
19S1Fish Audio434 ms4.9%10,236
20Flash v2.5ElevenLabs455 ms6.7%9,259
21Speech 2.8 HDMiniMax460 ms1,995
22Sonic 3.6Cartesia466 ms560
23Simba 3.2Speechify484 ms4.7%14,525
24Chirp 3 HDGoogle512 ms5.2%14,530
25Simba 3.0Speechify526 ms5.3%14,526
26Falcon 2Murf549 ms10,229
27Lightning v3.1 ProSmallest586 ms4.4%14,515
28Qwen3 TTS Flash RealtimeAlibaba645 ms8.8%14,530
29S2.1 Pro FreeFish Audio806 ms4.7%14,464
30GPT-4o mini TTSOpenAI1075 ms4.8%14,517
Under-sampled models are excluded; tied models share a place. Dotted WER values split into substitutions, deletions and insertions on hover or tap.

Latency vs accuracy

TTFA vs WEREach point is one measured model · Flash v2.5 highlighted · 30-day averagesTime to First Audio against Word Error Rate for every measured TTS model, with Flash v2.5 highlighted.
Palabra TTS v1 — 116 ms, 5.9%vui — 124 ms, 7.9%TTS Flash 2 — 128 ms, 4.9%TTS 2 — 176 ms, 4.8%Blizzard — 235 ms, 7.4%Neural — 236 ms, 4.3%Mist v3 — 256 ms, 6.3%TTS Rt v2 — 262 ms, 3.9%Sonic 3.5 — 274 ms, 6.1%TTS RT v1 — 275 ms, 3.7%Dragon HD Latest — 310 ms, 5.1%Coda — 313 ms, 5.2%Aura 2 — 328 ms, 5.3%S2.1 Pro — 374 ms, 4.6%Default — 384 ms, 4.6%Speech 2.8 Turbo — 411 ms, 4.8%Eleven v3 Conversational — 412 ms, 4.4%Grok TTS — 420 ms, 4.7%S1 — 434 ms, 4.9%Speech 2.8 HD — 460 ms, 4.7%Sonic 3.6 — 466 ms, 5.5%Simba 3.2 — 484 ms, 4.7%Chirp 3 HD — 512 ms, 5.2%Simba 3.0 — 526 ms, 5.3%Falcon 2 — 549 ms, 5.2%Lightning v3.1 Pro — 586 ms, 4.4%Qwen3 TTS Flash Realtime — 645 ms, 8.8%S2.1 Pro Free — 806 ms, 4.7%GPT-4o mini TTS — 1075 ms, 4.8%Flash v2.5 — 455 ms, 6.7%

Averages and tail latency

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

Flash v2.5 latency distributionMilliseconds · shared axis across metrics · last 30 daysFlash v2.5's latency percentiles per metric: p25–p75 band, p50 tick, whisker to p99.
  • Time to First Audiop50 204 ms · p99 3579 ms
  • TTFA Network Roundtripp50 161 ms · p99 3502 ms
  • TTFA Leading Silencep50 39 ms · p99 86 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 Audio455 ms189 ms204 ms225 ms407 ms2828 ms3579 ms9,259
TTFA Network Roundtrip392 ms152 ms161 ms175 ms311 ms2753 ms3502 ms5,889
TTFA Leading Silence40 ms31 ms39 ms50 ms60 ms69 ms86 ms5,889
Word Error Rate6.7%0.0%0.0%10.5%21.1%31.3%40.0%9,259

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 daysFlash v2.5's daily median Time to First Audio over the last 30 days.
Flash v2.5 · Jul 31: 204 msFlash v2.5 · Aug 1: 198 msFlash v2.5 · Aug 2: 208 msFlash v2.5 · Aug 3: 207 msFlash v2.5 · Aug 4: 199 msFlash v2.5 · Aug 5: 215 msFlash v2.5 · Aug 6: 203 msFlash v2.5 · Aug 7: 207 msFlash v2.5 · Aug 8: 207 msFlash v2.5 · Aug 9: 206 msFlash v2.5 · Aug 10: 206 msFlash v2.5 · Aug 11: 207 msFlash v2.5 · Aug 12: 209 msFlash v2.5 · Aug 13: 212 msFlash v2.5 · Aug 14: 214 msFlash v2.5 · Aug 25: 182 msFlash v2.5 · Aug 26: 189 msFlash v2.5 · Aug 27: 185 msFlash v2.5 · Aug 28: 181 ms
Word Error Rate — daily averageDaily average · UTC daysFlash v2.5's daily Word Error Rate over the last 30 days.
Flash v2.5 · Jul 31: 6.6%Flash v2.5 · Aug 1: 8.6%Flash v2.5 · Aug 2: 6.3%Flash v2.5 · Aug 3: 6.9%Flash v2.5 · Aug 4: 7.0%Flash v2.5 · Aug 5: 5.8%Flash v2.5 · Aug 6: 6.7%Flash v2.5 · Aug 7: 7.2%Flash v2.5 · Aug 8: 7.2%Flash v2.5 · Aug 9: 6.9%Flash v2.5 · Aug 10: 6.1%Flash v2.5 · Aug 11: 7.1%Flash v2.5 · Aug 12: 6.8%Flash v2.5 · Aug 13: 6.0%Flash v2.5 · Aug 14: 7.0%Flash v2.5 · Aug 25: 7.4%Flash v2.5 · Aug 26: 7.9%Flash v2.5 · Aug 27: 6.3%Flash v2.5 · Aug 28: 6.7%

Time to First Audio by dataset

Flash v2.5 by test conditionMilliseconds · lower is better · best condition firstFlash v2.5's Time to First Audio on each benchmark dataset.
  1. Text prompts455 ms
Time to First Audio per dataset, with the number of samples behind each figure.
DatasetTTFASamples
Text prompts455 ms9,259

Strongest condition: Text prompts at 455 ms · weakest: Text prompts at 455 ms.

Limits of this comparison

Coval's timing begins at the request and ends at audible speech, matching what a voice-agent caller experiences.

  • The public benchmark does not rank subjective naturalness, emotion fidelity or clone similarity.

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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