Anthropic's Claude Opus 5 costs well below Fable 5 while matching or beating it across most benchmarks
Quick Answer
Anthropic's Claude Opus 5 outperforms Fable 5 in multiple benchmarks while costing less, achieving a top score of 61 on the Artificial Analysis Intelligence Index.
Quick Take
It excels in coding tasks, tying for first place on the Coding Agent Index, and shows strong performance in knowledge work with a notable Elo rating of 1720.
Key Points
- Opus 5 scores 61 on the Artificial Analysis Intelligence Index, surpassing Fable 5's 60.
- In coding, Opus 5 ties for first place on the Coding Agent Index with 67 points.
- Cost per task for Opus 5 is $17.79, significantly lower than Fable 5's $22.30.
- Opus 5 achieves an Elo rating of 1720 on the AA-Briefcase benchmark, leading Fable 5 by 146 points.
- Factual accuracy remains a challenge for Opus 5, with a hallucination rate of 50%.
DeepSignal Analysis
What happened
Anthropic's Claude Opus 5 has been reported to outperform Fable 5 in several benchmarks while being less expensive. It achieved a score of 61 on the Artificial Analysis Intelligence Index and excels in coding tasks, tying for first place on the Coding Agent Index. However, its factual accuracy remains a concern, trailing behind Fable 5.
Key evidence
- Claude Opus 5 scored 61 on the Artificial Analysis Intelligence Index, surpassing Fable 5's score of 60.
- In coding tasks, Claude Opus 5 at 'xhigh' shares first place on the Coding Agent Index with Claude Code, achieving a score of 67.
- On the AA-Briefcase benchmark, Opus 5 reached an Elo rating of 1720, significantly higher than Fable 5's 1574.
Why it matters
The competitive performance of Claude Opus 5 at a lower cost suggests a shift in the AI landscape, where models may become more accessible and commoditized. This could influence pricing strategies and development priorities across the industry. However, the noted weaknesses in factual accuracy highlight ongoing challenges in AI reliability, which could impact user trust and adoption.
What to watch
Source Excerpt
Anthropic's Claude Opus 5 leads the Artificial Analysis Intelligence Index with 61 points, edging out Claude Fable 5 and GPT-5. 6 Sol. The model scores highest in analytical quality and coding, and costs up to half as much as Fable 5 at lower reasoning tiers. But the race at the top remains close.
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