METR puts Opus 4.5 at a 4h49m autonomy horizon

Claim

METR measured Claude Opus 4.5 at a state-of-the-art 50% autonomy time horizon of 4 hours 49 minutes, matching a fast-timeline AI 2027 variant in which each doubling is 15% easier.

Reported metric: 4h49m

Reporting date: 2025-12-20 (not necessarily the event date)

Sources

Attribution and reporting linked by this record; links do not imply independent verification.

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