Anthropic has released Sonnet 5.5, the newest version of its mid-tier model, positioning it as a faster and cheaper workhorse than its predecessor. The company claims Sonnet 5.5 runs 30 percent faster than Sonnet 5 and burns tokens at a significantly slower rate, making it well suited to everyday tasks such as coding and office document work. Sonnet 5, announced roughly three months earlier, had been pitched primarily for efficient agentic deployment; Sonnet 5.5 shifts the emphasis to speed while keeping costs in check.

In Anthropic‘s model hierarchy, Sonnet sits below Opus but can be more useful in certain circumstances because of its agility. Anthropic‘s benchmarks show Sonnet 5.5 outperforming Opus 5.5 on agentic coding, which the company attributes to its ability to spawn multiple agents without exceeding cost limits. The model is also said to have cyber capabilities comparable to Opus 5, and Anthropic says Sonnet 5.5 is the first Sonnet model subject to the same cyber safeguards applied to Fable and Opus.

The company plans to ship a new version of Haiku, its smallest model, in the coming weeks, though no firm date was given. The release lands amid a flurry of model launches from major AI labs: OpenAI released enhanced versions of Sol and Luna, its mid-tier and budget-friendly models, last week, and Meta announced a model tied to an upcoming smart glasses feature.