Model profile
Claude Opus 4.1
Deep reasoning on hard problems
AnthropicProprietaryNo. 4 overall
Editor's verdict
A specialist for architecture decisions, hard debugging, and high-stakes documents. Most teams rent it by the task, not by the day.
Where it wins
- Sustains multi-hour reasoning chains without losing the plot
- Careful, well-cited analysis of dense source material
Watch-outs
- Premium pricing hard to justify over Sonnet for routine tasks
- Slower response times under load