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The Humanness Index™
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The Humanness Index™

The open benchmark for how human voice AI sounds. Built and operated by Vapi.

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Code is Apache-2.0. Standings data is CC BY 4.0. Audio clips and source voices are licensed recordings, all rights reserved. Provider logomarks belong to their respective owners and are used nominatively. “The Humanness Index™” name and logo are Vapi trademarks; see TRADEMARKS.md.

  1. Humanness Index™
  2. ElevenLabs
  3. Turbo v2

Humanness Index™ · TTS model

ElevenLabs

Turbo v2

by ElevenLabs

Turbo v2 was ElevenLabs' first generation low latency model, an English only engine built to bring conversational agents under a latency bar its earlier models could not meet.

Rank
#14
Humanness
63
Likely rank
#7–17
Blind votes
102

Standings as of Jun 13, 2026, 00:15 UTC

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A real arena clip: a cloned source voice reading a customer support prompt at phone quality.

Turbo v2 key stats

Latency (measured)
302 ms1
Languages
English2
Price / 1M chars
$503
Released
20234
  1. Vapi streaming benchmark (50 trials per model) (checked 2026-06-10) Median of 50 sequential live streaming trials, June 2026; includes network RTT from the benchmark machine.
  2. elevenlabs.io/docs/overview/models (checked 2026-06-10)
  3. elevenlabs.io/pricing/api (checked 2026-06-10) ElevenAPI pay-as-you-go: Flash/Turbo $0.05 per 1k characters = $50 per 1M. Eleven v3 and Multilingual v2 bill $0.10 per 1k ($100 per 1M), encoded per model.
  4. elevenlabs.io/docs/overview/models (checked 2026-06-10, confidence: medium) Late 2023; ElevenLabs published no exact date.

Background

Turbo v2 was ElevenLabs' first generation low latency model, an English only engine built to bring conversational agents under a latency bar its earlier models could not meet. ElevenLabs now recommends the Flash family for new builds and describes Turbo v2 as functionally equivalent to Flash v2 but slower on average. It remains widely deployed in voice stacks built before Flash arrived, and it still posts a strong humanness showing on the Index.

Sources: elevenlabs.io

At a glance

Released in late 2023, Turbo v2 defined the first generation of the low latency tier ElevenLabs later rebuilt as Flash. In our 50 trial streaming benchmark it returned first audio in a median of 302 ms, the slowest of the four low latency ElevenLabs models on the Index.

Sources: elevenlabs.io

Position in the rankings

Standings as of Jun 13, 2026, 00:15 UTC

RankProviderModelHumannessLatency
#12MiniMaxMiniMaxSpeech 2 Turbo63315 ms
#13NeuphonicNeuphonicneu_hq63276 ms
#14ElevenLabsElevenLabsTurbo v263302 ms
#15InworldInworldTTS-1.5-max61337 ms
#16ElevenLabsElevenLabsMultilingual v2611006 ms

See the full Humanness Index™ rankings

Frequently asked questions

How is Turbo v2 tested on the Humanness Index™?
Listeners hear Turbo v2 against another model in a blind head to head round, both voices reading the same customer support prompt from the same cloned source voice, and they pick whichever sounds more human. Its Humanness score derives purely from those votes.
Which languages does Turbo v2 support?
Turbo v2 is English only. Its successor Turbo v2.5 extended the same latency tier to 32 languages.

Keep exploring

ElevenLabsElevenLabsAll ElevenLabs models on the IndexElevenLabsTurbo v2.5Rank #6 · Humanness 75ElevenLabsFlash v2Rank #17 · Humanness 57ElevenLabsFlash v2.5Rank #7 · Humanness 72ElevenLabsEleven v3Rank #5 · Humanness 76ElevenLabsMultilingual v2Rank #16 · Humanness 61

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