Anthropic has released Opus 4.5, its latest high-end model and strongest system to date, being the final 4.5 line-up.
The company confirmed that Opus 4.5 provides leading results in software engineering tests, becoming the first model to clear the 80% mark on the SWE-Bench Verified assessment.
It also recorded success in problem-solving tasks and computer-based performance, areas Anthropic has pushed aggressively in recent months.
Alongside the launch, the company is enhancing access to several products built around the model’s capabilities. Claude for Chrome will now be open to all Max users, while Claude for Excel is expanding to Max, Team and Enterprise customers. These tools were previously restricted to pilot testing.
Opus 4.5 introduces a redesigned memory system intended to improve long-running tasks and reduce disruptions during extended conversations. Users with paid plans will now be able to continue chats without being cut off when the system reaches its context limit, as the model compresses earlier exchanges quietly in the background.
Dianne Na Penn, Anthropic’s head of product management for research, noted the change in how the system handles information, saying: “There are improvements we made on general long context quality in training with Opus 4.5, but context windows are not going to be sufficient by themselves. Knowing the right details to remember is really important in complement to just having a longer context window.”
Anthropic has also framed the update as preparation for more advanced agent-style tasks, where Opus directs smaller models to complete complex work across documents and codebases.
Penn noted the need for stability in those scenarios, adding: “This is where fundamentals like memory become really important, because Claude needs to be able to explore code bases and large documents, and also know when to backtrack and recheck something.”
The release arrives during a crowded period in the sector, coming less than two weeks after OpenAI launched GPT 5.1 and shortly after Google rolled out Gemini 3 on November 18. All three companies are competing for enterprise customers seeking systems capable of specialised technical work.
Opus 4.5 is available through Anthropic’s apps, API and major cloud platforms. The company has also increased usage allowances for Max and Team Premium customers to support daily adoption.
Anthropic says more details on performance and safety testing are outlined in its system documentation, which states that Opus 4.5 is the most secure model the firm has produced so far.
