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Claude Sonnet 5.5 reports a 70.6% Terminal-Bench score and lower cost

anthropic.com 5 min read Editor score 8/10

Anthropic says Sonnet 5.5 runs 30%+ faster, costs up to 30% less, and scores 70.6% on Terminal-Bench 4.0 versus 10.3% for Sonnet 5. Engineers evaluating coding models get concrete claims about agentic performance, speed and cost.

What

Claude Sonnet 5.5 is a faster, lower-cost model for well-scoped tasks such as bug fixes and document creation.

How

It scores 70.6% on Terminal-Bench 4.0, versus 10.3% for Sonnet 5, and generates outputs over 30% faster.

Why it matters

Its speed and lower per-task cost make it a candidate for fast iteration on everyday engineering work.

Read on anthropic.com → Hacker News · 492 comments

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