Claude Sonnet 5.5 nears Opus performance while cutting task costs up to 30%

Anthropic has launched Claude Sonnet 5.5, the second model in its Claude 5.5 family, positioning it as a faster and cheaper option for coding, everyday work and document creation. The model generates output more than 30% faster than Sonnet 5 and costs up to 30% less per task in Anthropic’s testing, largely because it requires fewer tokens to complete the same work. Token pricing itself remains unchanged at $2 per million input tokens and $10 per million output tokens. Anthropic is pitching Sonnet 5.5 as a lower-cost complement to Claude Opus 5.5. While Opus remains targeted at complex and open-ended work requiring sustained judgment, Sonnet is designed for more clearly defined tasks, bug fixing and the creation of documents, slides and spreadsheets. The gap between the two models has narrowed significantly on some evaluations. Sonnet 5.5 outperformed Opus 5.5 on Terminal-Bench 4.0, scoring 70.6% versus 66.4%. On GDPval-AA, which measures real-world knowledge work, the two models were nearly tied, with Sonnet 5.5 scoring 1,844 compared with 1,846 for Opus 5.5. Anthropic said that at some effort settings Sonnet 5.5 performs comparably with Opus 5.5, although the company still conside...