Anthropic launches Claude Sonnet 5.5 with 30% increased speed

Anthropic has launched Claude Sonnet 5.5, which features a 30% increase in speed and approaches the capabilities of Opus. This launch follows the earlier update of Opus 5.5. Claude Sonnet 5.5 demonstrates strong performance, with test results closely resembling those of Opus 5.5, while being offered at a lower price point.

It surpasses comparable models such as GPT-6 Sol. The API pricing for Sonnet 5.5 remains at 2/10 USD per million tokens, and the cache reading cost is 0.2 USD per million tokens, making this aspect equivalent to Opus 5.5. The key advantage of Sonnet 5.5 is its increased speed and a 30% reduction in total tokens used to solve problems.

A significant change is that Anthropic has linked preserved thinking to user accounts to prevent distillation attacks that could extract Claude's capabilities to train other models. However, this measure may cause issues if there is a change in user accounts during the process.