Anthropic: Claude Haiku 5.5

Anthropic: Claude Sonnet 5.5

Claude Sonnet 5.5 is Anthropic’s upgraded Sonnet-class model, delivering stronger performance than Claude Sonnet 5 while running over 30% faster and at lower cost for many workloads. It is designed for agentic coding, tool use, and everyday professional tasks, making it well suited for developers and teams building fast, capable AI agents.

Anthropic: Claude Opus 5.5

Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code review and bug finding, financial and scientific analysis, and reading dense charts, diagrams, and screenshots, and it is more careful than its predecessor about only stating figures and citing sources it can back up. The model completes comparable tasks in fewer steps and with fewer tokens than Opus 5, and reports on its work in plainer language, with clear updates on what it did, what it found, and what it needs from the user. Thinking is always adaptive, so effort is the main lever for trading off depth, latency, and cost, and lower effort settings remain effective for latency-sensitive workloads.

Anthropic: Claude Fable 5.1

Claude Fable 5.1 is Anthropic’s latest model for demanding reasoning and long-horizon agentic work, with stronger performance in long-running coding, multistep research, and document, spreadsheet, and slide workflows. It supports text and image inputs, text output, a 1M-token context window, and adaptive thinking that is always on with effort-based steering.

Anthropic: Claude Opus 5

Claude Opus 5 is Anthropic’s flagship Opus-series model for advanced reasoning, coding, and high-value knowledge work, delivering frontier-level performance close to Claude Fable 5 at roughly half the cost. It supports text, image, and file inputs with text output, offers a 1M-token context window, and is well suited for complex software engineering, scientific research, and long-horizon agentic workflows.

Anthropic: Claude Sonnet 5

Claude Sonnet 5 is built to be the most agentic Sonnet model yet. It can plan, use tools such as browsers and terminals, and operate autonomously at a level that only recently required larger and more expensive models.

Anthropic: Claude Fable 5

Claude Fable 5 is Anthropic's Mythos-class model, designed for autonomous knowledge work and coding. It accepts text, image, and file inputs, produces text output, and features reasoning capabilities along with a 1M-token context window. The model excels at long-running, complex, and asynchronous tasks that once demanded frequent human oversight. Its core strength lies in handling end-to-end work that would typically take a person hours, days, or even weeks — tackling problems that are extended, ambiguous, or involve many interdependent steps. It carries out well-defined tasks with minimal errors, self-corrects through built-in verification loops, and comes with robust safeguards.