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Claude Opus 5.5 launched, first model in the Claude 5.5 family

Tech · Releases · Tue, September 22, 2026

Source

Anthropic launched Claude Opus 5.5, the first model in the Claude 5.5 family. It performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5.

Every year

DateEventWhen
Jun 30, 2026Claude Sonnet 5 launched3 mo ago
Jul 1, 2026Model entitlements for Enterprise plans (beta)3 mo ago
Jul 9, 2026Monthly recap in Settings > Reflect (beta), plus break reminders and quiet hours3 mo ago
Jul 24, 2026Claude Opus 5 launched2 mo ago
Aug 6, 2026Skill and plugin security scanning (beta) for Enterprise plans2 mo ago
Sep 1, 2026Claude Fable 5.1 and Claude Mythos 5.1 launched24 days ago
Sep 10, 2026Smart reports (beta) on Claude Enterprise analyze team usage and costs15 days ago
Sep 15, 2026Salesforce in Claude plugin (beta) with 37 pre-built sales skills10 days ago
Sep 22, 2026Claude Opus 5.5 launched, first model in the Claude 5.5 family3 days ago

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anthropic
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anthropic
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Changes
  • 2026-09-25: added to 2026-09-22

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