Inworld
inworld-tts-2
Measured 2026-07-03
Run inworld-tts-2 on Speko →One API, every model on this board.
Naturalness
1561
Win % · 95% CI
63%
57–69%
Drift
9
Measured 2026-10-30
Synth p50
116ms
116–125 p50–p90
Robustness
0.82
Fined:
• fatal · ordinals (×0.5) — never said “one thousandth” (7 of 7 transcripts)
→ we sent “This is our 1,000th order.”
→ it said “This is our one-zero-th order.”
• minor · times · promptable — said “slash” out loud (4 of 7 transcripts)
→ we sent “Meet at 8:45 a.m. PT / 11:45 a.m. ET.”
→ it said “Meet at eight forty-five AM Pacific Time, slash eleven forty-five AM Eastern Time.”
• minor · dates · promptable (international, ×0.4) — said “slash” out loud (5 of 7 transcripts)
→ we sent “The lease ends 2025/06/30.”
→ it said “The lease ends two thousand 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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