#01SOTAAnthropic· released 2026-09-01

Anthropic: Claude Fable 5.1.

Claude Fable 5.1 improves on Claude Fable 5 across the board, with the biggest gains in agentic coding, long-running agentic workflows, and knowledge work: long code refactors, front-end and visual...

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Context
1.0M
Input $/1M
$10.00
Output $/1M
$50.00
Modality
text · image · file

Benchmarks

How these are aggregated →
Arena Elo
1638
LMArena — human blind votes
AA Index
71.0
Artificial Analysis composite
LiveBench
91.1
Contamination-resistant
GPQA
93.7%
Grad-level science reasoning
MMLU-Pro
91.2%
Broad knowledge
SWE-bench
86.1%
Real GitHub bugs (Verified)
Terminal-Bench
77.4%
Agentic shell tasks
ARC-AGI
43.8%
Abstract reasoning
Aider Polyglot
89.6%
Multi-language code editing
Speed
63 tok/s
Median output speed

Profile

Anthropic: Claude Fable 5.1 is Anthropic's entry at position #1 on the current aggregated leaderboard. Its strongest signals are human preference voting, graduate-level science reasoning, real-world software engineering, and unattended agentic work. Every figure below is aggregated from the public sources listed on the homepage and refreshed on each pipeline run.

The score spread is comparatively complete for this model, but the standing advice still applies: treat gaps of a few points as ties and validate on your own workload before committing.

How this model's position is computed is documented in the methodology; what each benchmark actually measures is in the benchmark guide. See a figure that disagrees with its source? Report it — accepted corrections apply on the next refresh.

Nearby on the leaderboard