Claude Fable 5 tops the Artificial Analysis Intelligence Index and sets new highs across several benchmarks. But the gain over its predecessor might be slim, while costs more than double.
Anthropic's new flagship model, Claude Fable 5, scores 64.9 points in the Artificial Analysis Intelligence Index, claiming first place. The gap to the best non-Anthropic model, GPT-5.5, is about five points. Anthropic now holds the top two spots on the leaderboard.
Claude Fable 5 takes the lead in the Artificial Analysis Intelligence Index with 64.9 points. | Image: Artificial Analysis
That crown comes at a cost. Fable 5 runs $10 and $50 per million input and output tokens, double Opus 4.8's $5 and $25. A full index run hits $9,940, versus $4,970 for Opus 4.8 at max reasoning. That premium buys a 5.7 percent performance gain. Opus 4.8 and 4.7 already followed the same pattern versus Opus 4.6, with steep price bumps for small gains. Anthropic itself called 4.8's improvement over 4.7 "modest but tangible."
A full Artificial Analysis Intelligence Index run costs nearly $10,000 with Fable 5. Opus 4.8 came in at just under $5,000 with roughly 5.7 percent less performance. | Image: Artificial Analysis
