Anthropic Claud Opus 4.6 gets ‘Fast Mode’: What is it and how it is different from standard mode

Days after launching its latest flagship model Opus 4.6, Anthropic has introduced “Fast Mode” for the LLM with the basic functionality – to provide significantly quicker response times for complex reasoning and software development tasks. The rollout comes as Anthropic gains broader mainstream recognition beyond the technology sector, such as Goldman Sachs infusing the AI company’s AI solution in their operations. According to Anthropic, the new mode can deliver responses up to 2.5 times faster than the standard version of Claude Opus 4.6. Currently in a limited research preview, Fast Mode is being offered as an early experiment through the Claude Developer Platform (API) and Claude Code.“Our teams have been building with a 2.5x-faster version of Claude Opus 4.6. We’re now making it available as an early experiment via Claude Code and our API,” the company said in a post on X.Apart from highlighting its prowess in undertaking tasks quickly, Anthropic also announced that running the fast mode is going to be pricier than the standard mode.“Fast mode is more expensive to run. It’s for urgent, high-stakes projects, combining impressive speed with Opus-level intelligence,” the company stated in a separate post on X.With this mode, Anthropic aims to take on Gemini 3 Flash which also offers fast responses as compared to Gemini 3. According to Google, Gemini 3 Flash is up to 3 times faster than Gemini 2.5 Pro, with Gemini 3.0 mainly recommended for “complex reasoning, multimodal and vision understanding and agentic and vibe coding tasks.”However, unlike Claude Opus 4.6 Fast Mode, Google Gemini 3 Flash is cost effective.“Gemini 3 Flash retains this foundation, combining Gemini 3's Pro-grade reasoning with Flash-level latency, efficiency and cost. It not only enables everyday tasks with improved reasoning, but also is our most impressive model for agentic workflows,” the company added.Claude Opus 4.6 serves as Anthropic's most capable model to date, featuring improved planning capabilities and the ability to manage long-running, autonomous tasks.