Inworld
inworld-tts-2
Measured 2026-07-03
* Conditional
Re-benchmarked 2026-09-03: drift and robustness. Naturalness and time-to-first-audio are unchanged.
Naturalness
1561
Win % · 95% CI
63%
57–69%
Drift
10
Synth p50
116ms
116–125 p50–p90
Robustness
0.93
Fined:
• minor · dates — said “slash” out loud; a prompt fixes this (4 of 7 transcripts)
→ we sent “The deadline moved to 10/02.”
→ it said “The deadline moved to 10. Slash zero two.”
• minor · dates — kept the value but never said “march”; a prompt fixes this (4 of 7 transcripts)
→ we sent “Your slot is 03/09 this year.”
→ it said “Your slot is zero three zero nine this year.”
• minor · dates (international, ×0.4) — said “slash” out loud; a prompt fixes this (4 of 7 transcripts)
→ we sent “The lease ends 2025/06/30.”
→ it said “The lease ends twenty twenty five slash zero six slash thirty.”
Cost / 1M chars
$25.0
On-demand. Drops to $20 on Creator and $12.50 on Growth.
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