Smallest
lightning_v3.1
Measured 2026-07-03
Run lightning_v3.1 on Speko →One API, every model on this board.
Naturalness
1544
Win % · 95% CI
58%
51–64%
Drift
det
Synth p50
173ms
173–193 p50–p90
Robustness
0.25
Fined:
• fatal · currency — dropped the minus sign (7 of 7 transcripts)
→ we sent “The balance is -$12.50.”
→ it said “The balance is $12.50.”
• fatal · math operators — never said “divided” (6 of 7 transcripts)
→ we sent “That is 100÷4=25 per person.”
→ it said “That is $134 equals 25 per person.”
• fatal · currency (international, ×0.4) — dropped the minus sign (7 of 7 transcripts)
→ we sent “Balance: -€45,90 outstanding.”
→ it said “Balance: 45 euros and 90 cents outstanding.”
+ 6 more fined
Not re-measured: v1.3 only (125 fixtures), score held at its last published value. Smallest refuses English from our account (LANGUAGE_NOT_ENABLED_IN_REGION), so the v1.4/v1.5 fixtures could not run, and re-scoring the old fine on the new curve (0.47) would rank an untested row above re-tested ones.
Cost / 1M chars
$17.5
Pay-as-you-go; $0.175/10k chars (smallest.ai/pricing/models).
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