Voice AI BenchmarksBy

PROVIDERLAST 30 DAYS

official resource

LMNT voice AI models and benchmarks

LMNT develops low-latency speech synthesis APIs and custom voices.

Measured models
1
TTS
Best TTS model#5 / 30
235ms
Blizzard

Overview

LMNT's TTS endpoint offers multilingual synthesis and voice cloning.

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

Text-to-Speech
Blizzard

Text-to-Speech

Full TTS dashboard

Ranked on Time to First Audio against 30 measured models.

Time to First Audioms · lower is better · LMNT models markedEvery measured TTS model on Time to First Audio, with LMNT's models 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
leaders plus LMNT models · 23 other models in the full table
Word Error Rate% · lower is better · LMNT models markedEvery measured TTS model on Word Error Rate, with LMNT's models highlighted.
  1. #1TTS RT v13.7%
  2. #2TTS Rt v23.9%
  3. #3Neural4.3%
  4. #4Eleven v3 Conversational4.4%
  5. #5Lightning v3.1 Pro4.4%
  6. #6Default4.6%
  7. #7S2.1 Pro4.6%
  8. #28Blizzard7.4%
leaders plus LMNT models · 22 other models in the full table
TTFA vs WER — LMNT vs every measured modelEach point is one measured TTS model · LMNT models highlighted · 30-day averagesTime to First Audio against Word Error Rate for every measured TTS model, with LMNT's models 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%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%Flash v2.5 — 455 ms, 6.7%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%Blizzard — 235 ms, 7.4%
Benchmarked models with their Time to First Audio over the last 30 days.
ModelHostTTFARank
BlizzardLmnt235 ms5th of 30

Limits of this comparison

Coval measures the Blizzard model through LMNT's own infrastructure.

  • The benchmark does not rate custom-voice similarity or every LMNT voice and language.

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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