Model releaseLimited global significanceConfirmed confidence
Anthropic releases Claude Opus 4.1
Anthropic releases Claude Opus 4.1, an incremental closed-model update tuned for complex mathematics and long reasoning chains.
What happened
Event details
Released on August 5, 2025, Claude Opus 4.1 is a closed autoregressive Transformer and a targeted update to the Opus line. Anthropic did not disclose its parameter count.
Assessment
Why it matters
The release refines Anthropic's top-tier model for demanding mathematical and extended reasoning workloads without representing a full generational shift.
45/100Global significance score. Regional effects are recorded only when the evidence supports a meaningful difference.
Availability
Access notes
Available as a closed Anthropic model.