Language modelLimited access
Claude Mythos 5.1
Anthropic
- Released
- September 1, 2026
- Data date
- September 2, 2026
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Position within the category
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This model does not yet have enough published values for an overall rank. It covers 0 of 4 required comparison cohorts.
- Coverage
- 0 / 4
Leaderboard
1Claude Opus 588.9 / 100
2Gemini 3.8 Flash88.5 / 100
3Claude Fable 583.2 / 100
25MiMo-V2.5-Pro12.5 / 100
—Claude Mythos 5.1, Current modelNot ranked
Profile
Specifications and access
Published information about this model. Unknown values are not estimated.
- Model type
- ProprietarySource
- Context window
- 1,000,000 tokensSource
- Knowledge cutoff
- June 2026Source
- Notes
- Released September 1, 2026. Shares the model, specifications, and pricing of Fable 5.1, but uses fewer restrictive safeguards. Available by invitation only through Project Glasswing. Official API ID: claude-mythos-5-1.Source
Pricing
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Evidence
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