All model families · Shutdown calendar
Claude Mythos 5.1 deprecation & shutdown dates
2 Claude Mythos 5.1 versions tracked across 2 providers. Next shutdown: claude-mythos-5-1 on Anthropic, Sep 1, 2027 (earliest).
Last checked 2026-10-18 on the official deprecation pages.
Every Claude Mythos 5.1 version on every provider we track, with the date and replacement each official deprecation page gives.
| Model ID | Provider | Status | Shutdown | Replacement |
|---|---|---|---|---|
claude-mythos-5-1 | Anthropic | active (earliest retirement date) | Sep 1, 2027 (earliest) | None listed by provider |
claude-mythos-5-1 (1) | Azure OpenAI | active (no shutdown date announced) | — | None listed by provider |
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Frequently asked questions
When is Claude Mythos 5.1 being deprecated?
2 Claude Mythos 5.1 versions tracked across 2 providers. Next shutdown: claude-mythos-5-1 on Anthropic, Sep 1, 2027 (earliest).
What replaces Claude Mythos 5.1?
No replacement is named on the official pages.
When does claude-mythos-5-1 on Anthropic shut down?
claude-mythos-5-1 on Anthropic shuts down no earlier than Sep 1, 2027. The provider lists no replacement.
When does claude-mythos-5-1 (1) on Azure OpenAI shut down?
Azure OpenAI lists claude-mythos-5-1 (1) as active (no shutdown date announced) with no shutdown date published. The provider lists no replacement.