Anthropic Cyber Big Closed weights

Claude Mythos 5

156 days since Anthropic announced it · 9 Jun 2026

Claude Mythos 5 is a closed-weights cyber model from Anthropic, announced 9 Jun 2026. It costs $10 per 1M input tokens and $50 per 1M output tokens.

Input: $10; per 1M tokens
Cache write: —; per 1M tokens
Cache read: —; per 1M tokens
Output: $50; per 1M tokens
Context window: —; tokens
Parameters: —; not disclosed

Announcement: anthropic.com/news/claude-fable-5-mythos-5

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Anthropic · Big · Mythos

closed weights

Claude Mythos 5.2 +55d 9 Nov 2026
Claude Mythos 5.1 +98d 15 Sep 2026
Claude Mythos 5 9 Jun 2026

More from Anthropic

All models

Claude Fable 5.2 9 Nov 2026
Claude Haiku 5.5 7 Oct 2026
Claude Sonnet 5.5 28 Sep 2026
Claude Opus 5.5 22 Sep 2026
Claude Fable 5.1 1 Sep 2026
Claude Opus 5 24 Jul 2026
Claude Sonnet 5 30 Jun 2026
Claude Fable 5 9 Jun 2026

Facts last updated 7 Nov 2026, from Anthropic’s own pages.