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Anthropic's Claude Sonnet 5.5 nearly matches Opus 5.5 on benchmarks while costing up to 30 percent less per task

Sonnet 5.5 cuts costs 30% while nearly matching Opus on benchmarks—the efficiency tier just got competitive.

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The KeyNews take

Why it matters

Anthropic's mid-tier model now delivers near-flagship performance at lower cost and faster speed, reshaping the price-to-capability curve and forcing buyers to reconsider their tier selection. This is a direct response to OpenAI's GPT-6 family scaling.

The key facts

6 to know
  1. Claude Sonnet 5.5 released; Haiku 5.5 coming soon—completing Anthropic's answer to GPT-6 trio

  2. Output speed: 30% faster than prior Sonnet version

  3. Cost: up to 30% less per task than Opus 5.5

  4. Benchmark performance: nearly matches Opus 5.5 on knowledge-work benchmarks

  5. Coding benchmark (Terminal-Bench): 10.3% → 70.6% jump

  6. Positioned as efficiency alternative to flagship Opus 5.5

The story so far

Earlier coverage of this storyline

  1. Claude Opus 5.5 now available on AI GatewayVercel Blog
  2. Claude Opus 5.5 is now available on AWSAWS Machine Learning Blog
  3. Anthropic releases Claude Opus 5.5 and OpenAI counters with two cheaper GPT-6 modelsSiliconAngle
  4. Anthropic Launches Claude Opus 5.5 With Lower Prices and Faster OutputTechRepublic
  5. Anthropic releases Sonnet 5.5, which it calls a significantly cheaper, faster work partnerTechCrunch AI
  6. This story

Go to the source

The Decoderthe-decoder.com

Publisher excerpt: Anthropic has released Claude Sonnet 5.5, the second model in its Claude 5.5 family. It generates output more than 30 percent faster, costs up to 30 percent less per task, and nearly matches Opus 5.5 on knowledge-work benchmarks. On Terminal-Bench, a coding benchmark, the model jumps from 10.3 to…
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