Humanity's Last Exam

Two models, one price tag: $10 per million input tokens, $50 per million output tokens. GPT-6 Astra shipped on September 3, Claude Fable 5.1 on September 1. Identical sticker prices, so the comparison looks simple. It is not. The sticker is the same, the bill is not. Run the same work through both and what you pay can double or halve depending on the shape of your workload. This post starts with where that gap comes from, then walks the benchmark table, and finishes with three concrete billing scenarios. ...

On September 1, 2026, Anthropic released Claude Fable 5.1 and Claude Mythos 5.1. It has been roughly three months since Claude Fable 5 launched, and this time there is no government directive and no surprise shutdown in the story. The headline is different: the sticker price did not move, but the cost of actually running the model dropped sharply. On top of that, Fable 5.1 beats last month’s Claude Opus 5 on every benchmark Anthropic published. Let’s look at the details. ...

Anthropic today announced Claude Opus 5, the new flagship of the Claude family. The model brings a major jump over Opus 4.8 in agentic coding, knowledge work, computer use, and scientific research. Best of all, these gains ship at the same price. Let’s look at what the new model offers and where it stands against its rivals 🚀 What Is Claude Opus 5? Opus 5 is Anthropic’s most capable general-access model to date. Replacing Opus 4.8 , it shines especially in complex, long-horizon agentic tasks. ...

Hello everyone! 🚀 Anthropic has made waves in the AI world once again! Announced on February 5, 2026, Claude Opus 4.6 emerges as the company’s smartest model to date. So what new features does this model bring? Let’s dive in! 😊 What is Claude Opus 4.6? Claude Opus 4.6 is the latest member of Anthropic’s Opus family. Surpassing its predecessor Claude Opus 4.5 in many areas, this model offers significant improvements especially in coding, long-running agentic tasks, and working with large codebases. ...