Claude Fable 5.1 Price

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. ...