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Sonnet 5.5: Anthropic's mid-tier model now 30% faster at the same sticker price

Anthropic just sped up its workhorse Sonnet without raising the sticker price — and quietly put cyber safeguards on a mid-tier model for the first time. THE GIST Anthropic released Claude Sonnet 5.5 on 28 Sep 2026 at $2/$10 per million tokens, same as Sonnet 5. It claims about 30% more speed and up to 30% less cost per typical workload. Live on Claude.ai, AWS, Google Cloud, and Microsoft Foundry. THE TAKE Same list price, less burn: that's how you undercut Opus without a sal

THE HOOK

Anthropic just sped up its workhorse Sonnet without raising the sticker price — and quietly put cyber safeguards on a mid-tier model for the first time.

THE GIST

Anthropic released Claude Sonnet 5.5 on 28 Sep 2026 at $2/$10 per million tokens, same as Sonnet 5. It claims about 30% more speed and up to 30% less cost per typical workload. Live on Claude.ai, AWS, Google Cloud, and Microsoft Foundry.

THE TAKE

Same list price, less burn: that's how you undercut Opus without a sales slide. Putting Opus-class cyber safeguards on Sonnet admits useful agents are attack surface now. Speed is the product. The safety tax is the receipt.

OPINION

Reuters frames this as lineup-building ahead of a planned IPO, with Sonnet as the cheaper complement to last week's Opus 5.5. TechCrunch notes Anthropic's agentic-coding benches favour Sonnet over Opus when you spawn multiple agents under a cost cap — see TechCrunch and Reuters.

  • Story type: Breaking news
  • Impact: High
  • Confidence: High (official announcement)
  • Audience: Developers
  • What changed: Anthropic shipped Sonnet 5.5 at unchanged $2/$10 pricing with claimed 30% speed and lower per-task cost
  • What to watch: Haiku 5.5 timing and whether Sonnet displaces Opus for multi-agent coding spend
  • Reading time: 2 minutes

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