Anthropic · Claude Fable line · flagship
Claude Fable 5 was released by Anthropic on June 9, 2026, as a flagship model in the Claude Fable line.
Anthropic's new top-end model scores 80.3% on SWE-bench Pro (Anthropic gives one figure for Fable 5 and Mythos 5), up from 69.2% for Opus 4.8, at twice the price.
Compared with Claude Opus 4.8 · Anthropic's previous top model
Solves 8 in 10 hard real-world coding tasks
SWE-bench Pro — fixing real bugs in real software projects (one shared figure for Fable 5 and Mythos 5)
80.3%
▲ up from 69.2% · +11 points
More than doubles its score on the hardest coding tasks
FrontierCode Diamond — Cognition's 50 hardest tasks, graded on whether a maintainer would merge the code (one shared figure for Fable 5 and Mythos 5)
29.3%
▲ up from 13.4% · more than doubled
Costs developers twice as much to run
Price per 1M tokens — what developers pay, input / output
$10 / $50
price doubled — was $5 / $25
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Claude Fable 5.1 is the current model in this line. The card shows how long it has been since the last release against the line's usual gap and its recent ones — the rhythm, not a date.
Latest: Claude Fable 5.1 · Sep 1, 2026
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