Ailyre

Model release · Anthropic

claude-sonnet-5-5

Released
Review updated

Second Claude 5.5 family model (2026-09-28); ~30%+ faster output vs Sonnet 5 and up to ~30% lower cost per typical task; same list price as Sonnet 5: $2/$10 /MTok (cache write $2.50; cache reads cut from $0.20 to $0.10 on Oct 7, 2026); Adaptive thinking (default effort High on API / Medium in apps); large coding & knowledge-work gains vs Sonnet 5; ships with Opus-class cyber safeguards + preserved thinking; Haiku 5.5 launched Oct 7, 2026

Availability

Claude API/Platform claude-sonnet-5-5; Amazon Bedrock / Google Cloud / Microsoft Azure; Claude.ai / Claude Code apps; Cursor

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Introducing Claude Sonnet 5.5

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Models overview — Claude Sonnet 5.5 specs

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Claude Platform release notes — October 7, 2026 (Sonnet 5.5 cache read price)

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Pricing — cache read 0.05x on Sonnet 5.5 ($0.10)

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Introducing Claude Haiku 5.5 — Further updates

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