September 28, 2026 Understand what changes. Find what to use.

ModelsNews1 source

Anthropic releases Sonnet 5.5, says model is 30% faster

Anthropic released Sonnet 5.5, the latest version of its mid-range model, for tasks such as coding and creating office documents. The company says it responds 30% faster than Sonnet 5 and has a significantly lower token-burn rate. Anthropic’s benchmarks show Sonnet 5.5 outperforming Opus 5.5 on agentic coding, possibly because it can spawn multiple agents without exceeding cost limits.

Anthropic also says the model has cyber capabilities comparable to Opus 5. It therefore describes Sonnet 5.5 as the first Sonnet model to receive the same cyber safeguards applied to Fable and Opus. The company plans to release a new version of Haiku in the coming weeks but did not provide a firm date.

Why it matters · editorial interpretation

The combination of higher speed, lower token usage and claimed performance in agentic coding could make Sonnet 5.5 a more efficient option for development workflows involving multiple agents. Its cyber capabilities, which Anthropic says are comparable to Opus 5, and the safeguards the company applies also make security a central part of the update.

Sources

Code

One story, many sources

Coverage of the same story gathered in one item, with a link to each original.

Summary and interpretation apart

What the sources say stays in the summary; editorial context is labeled separately.

Made with AI, with sources

Summaries and translations generated with AI from the original stories, always linked.