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ModelsSimon Willison·· 18 days agoPicks

Anthropic releases Claude Sonnet 5.5

Claude Sonnet 5.5

Who
anthropic
When

What happened

Anthropic has released Claude Sonnet 5.5. The company says it runs more than 30% faster and costs up to 30% less on most tasks. It retains Sonnet 5's pricing while outperforming its predecessor across benchmarks.

Why it matters

The author tests Sonnet 5.5's coding performance and availability on the free tier, and compares it directly with Opus 5.5.

Reported by 4 sources

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