Model specification · Anthropic

Claude Fable 5.1

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...

SpecificationsReported values
Context window
1M
Maximum output
128K
Architecture
text+image+file->text
Tokenizer
Claude
Knowledge cutoff
—
Moderated
Yes
Input modalities
textimagefile
Output modalities
text
Full pricingUSD where reported
PriceStandard
Input$10.00 / M
Output$50.00 / M
Benchmark indexesReported indexes
Intelligence
53.4
Coding
81.6
Agentic
57.9
Design Arena Elo
1335
Example workload costsStandard pricing only
WorkloadInput / outputCache shareEstimated cost
Quick check10K / 1K × 10%$0.150
Long analysis100K / 4K × 150%$0.712
Workday20K / 2K × 1,00030%$241.50
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