Claude Opus 5.5 Released — Anthropic's New AI Model (BD Guide)

Quick answer

Claude Opus 5.5 is Anthropic's new AI model, released Sep 22. We’re introducing Claude Opus 5.5, the first model in our new Claude 5.5 family. It performs at the level of Claude Fable 5. From Bangladesh, use it with Claude Pro — see plans →

Key features

• It’s the new leading model, and early testers saw large jumps in performance on their most complex work.
• Vetted organizations can apply today to our Life Sciences Verification Program to use Opus 5.5 for biology research.
• Opus 5.5 also generates output more than 30% faster than Opus 5.
• We’re also providing subscription users a rate limit reset, which you can now save and use whenever you choose.
• Opus 5.5 communicates more naturally than prior models.

Details

Performance. Opus 5.5 is a major step up from Opus 5. It’s the new leading model, and early testers saw large jumps in performance on their most complex work. One tester completed a 680,000-line code migration in less than a day—work that would have taken an engineering team weeks. It’s good at finding and fixing inefficiencies in software: when we asked it to cut load times across every page of a web app, Opus 5.5 succeeded 39 of 40 times, while Opus 5 made smaller improvements that also altered the app’s behavior. A different tester had several Claude models build a game from a single prompt; Opus 5.5 scored higher than any other model on the strength of its graphics and polish.

Safety. Opus 5.5 achieves the best scores of any model to date on our automated behavioral audit, our alignment suite that tests Claude across thousands of simulated scenarios. It is much less likely than recent models to take hard-to-reverse actions or act outside the boundaries it’s been given, and it’s more resistant than Opus 5 to prompt injection. We’ve also broadened our alignment testing to cover longer tasks, impossible tasks, and scenarios modeled on real incidents, though it still has limits. Full details of our evaluation are available in the Opus 5.5 System Card.

Because Opus 5.5 is comparable to Claude Mythos 5.1 in biology and cybersecurity, we’re deploying it with safeguards similar to those on Claude Fable 5.1. Vetted organizations can apply today to our Life Sciences Verification Program to use Opus 5.5 for biology research. In the coming weeks we will also be expanding access to our Cyber Verification Program, and verified cybersecurity practitioners will be able to use Opus 5.5 for their work.

Use Claude Opus 5.5 from Bangladesh

Order Claude Pro with bKash, Nagad or Rocket — delivered in about 15 minutes with a private tracking page. Check Claude Pro plans and live prices →