Claude Fable 5.1 vs Claude Opus 5.5
27 SHARED BENCHMARKSAcross 27 shared benchmarks, Claude Fable 5.1 scores higher on 2 and Claude Opus 5.5 on 24, with 1 level. The widest gap is Terminal-Bench 4.0, where Claude Opus 5.5 scores 66.4 against 55.8. Claude Opus 5.5 is the cheaper of the two on tracked API pricing ($4.00 against $10.00 per million input tokens).
At a glance
Release dates per the vendor's own announcement. Prices: Anthropic's own price page for Claude Fable 5.1; Artificial Analysis for Claude Opus 5.5. ◆ = independently verified score.
Where each leadsby capability area · benchmark wins
Biggest gaps
Claude Fable 5.1 pulls furthest ahead on
No ratified-area lead of 3 points or more.
Claude Opus 5.5 pulls furthest ahead on
- Humanity's Last Exam67.7 vs 58.7
- SWE-bench Pro89.9 vs 81.2
- SWE-bench Multilingual93.9 vs 89.1
Every shared benchmark27 · grouped by area
Reasoning 1
Coding 2
Other shared benchmarks 24
Each score is the one the model's own page shows — the most authoritative tracked result for that benchmark, on the benchmark's standard methodology (source-attributed). ↓ marks lower-is-better metrics; ◆ an independently verified score. Open either model for its full surface, provenance and pricing. Quoted rates are the price-setter row we currently track for each model — its direct or vendor-official listing where one exists (anthropic-official, direct), otherwise the lowest tracked offer.