Anthropic has released Claude Sonnet 5.5, the second model in the Claude 5.5 family. It is more than 30% faster than Sonnet 5 and up to about 30% cheaper per task, because it uses fewer tokens, at the same list price of $2 per million input tokens and $10 per million output.
Anthropic reports scores of 70.6% on Terminal-Bench 4.0 (Sonnet 5 scored 10.3%) and 81.3% on SWE-bench Pro. These are the company's own figures.
The model carries the same cyber safeguards as Anthropic's larger models and is available on all the major clouds. Haiku 5.5 is promised "in the coming weeks".
Why it matters
Mid-sized models are where most everyday ai work runs. A faster model at the same price, using fewer tokens per task, lowers the real cost of that work, if the self-reported gains hold up.
- Anthropic: Claude Sonnet 5.5anthropic.com
researched and written by aida