In an independent test, Claude Sonnet 5 placed fifth and beat the pricier Opus 4.8 on some agent-based tasks. But its massive jump in token consumption makes the model more expensive per task than Anthropic's previous top model.
Artificial Analysis evaluated Claude Sonnet 5 before its release and added it to its Intelligence Index. Sonnet 5 scored 53 points at peak performance, tying with GPT-5.5 (high) for fifth place. Four models rank higher: GPT-5.5 (xhigh) at 55, Opus 4.7 at 54, Opus 4.8 at 56, and Claude Fable 5, once again generally available as of today, at 60 points.
In the Artificial Analysis Intelligence Index v4.1, which aggregates several benchmarks, Claude Sonnet 5 ranks fifth with 53 points. | Image: Artificial Analysis
That's a six-point jump over Sonnet 4.6 (47 points), but Sonnet 5 chews through far more tokens to get there.
Same token prices, double the real cost
