Claude Sonnet 5.5: 30% faster, up to 30% cheaper per task
Anthropic's new mid-tier: 70.6% on Terminal-Bench 4.0 (vs 10.3% for Sonnet 5), 46.2% FrontierCode 1.1 max-effort, 80.1% computer use, and near-Opus GDPval-AA (1,844 vs 1,846). Same $2/$10 per Mtok pricing, fewer tokens per task.
Why it matters
The mid-tier just ate most of the flagship's territory for well-defined work: batches tool calls more efficiently, sustains multi-hour coding sessions, and beats Sonnet 5 by 7x on terminal tasks while costing up to 30% less per task.
What you could build with it
A team running high-volume summarization or ticket triage can move those passes to Sonnet 5.5 and get near-top-tier quality at a mid-tier price.
First spotted on newsletter: source.
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