Anthropic Unveils Opus 4.5 with Enhanced Chrome and Excel Integrations
On November 24, 2025, Anthropic introduced Opus 4.5, the latest iteration of its flagship AI model. This release marks the culmination of the 4.5 series, following the earlier launches of Sonnet 4.5 in September and Haiku 4.5 in October.
Opus 4.5 sets a new benchmark in AI performance, excelling across various domains. It has achieved state-of-the-art results in coding assessments such as SWE-Bench and Terminal-bench, tool utilization tests like tau2-bench and MCP Atlas, and general problem-solving evaluations including ARC-AGI 2 and GPQA Diamond. Notably, Opus 4.5 is the first model to surpass an 80% score on the SWE-Bench verified coding benchmark, underscoring its advanced capabilities in software development tasks.
In tandem with the Opus 4.5 release, Anthropic has expanded the availability of its Claude for Chrome and Claude for Excel products. Previously in pilot phases, these tools are now accessible to a broader user base. The Chrome extension is available to all Max subscribers, while the Excel integration is offered to Max, Team, and Enterprise users. These integrations are designed to enhance user productivity by seamlessly incorporating AI assistance into everyday applications.
A significant advancement in Opus 4.5 is its improved memory management for handling long-context operations. This enhancement allows the model to process extensive information more effectively. Dianne Na Penn, Anthropic’s head of product management for research, emphasized the importance of this development, stating, “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.”
This refined memory capability has also enabled the introduction of the endless chat feature for paid Claude users. This feature allows conversations to continue without interruption when the model reaches its context window limit. Instead of halting, the model compresses its context memory seamlessly, ensuring a fluid user experience without notifying the user of the compression process.
The enhancements in Opus 4.5 are particularly geared towards agentic use cases, where the model functions as a lead agent orchestrating tasks among sub-agents powered by Haiku. Effective management of such tasks necessitates robust working memory, a challenge that Opus 4.5 addresses with its improved memory architecture. Penn elaborated on this, noting, “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 of Opus 4.5 positions Anthropic competitively in the AI landscape, especially against recent frontier models like OpenAI’s GPT 5.1 and Google’s Gemini 3. With its advanced performance metrics and enhanced integrations, Opus 4.5 is poised to offer users a more efficient and seamless AI experience across various applications.
