2 posts tagged with "Sonnet"

Anthropic released Claude Sonnet 5 on June 30, 2026, positioning it as the most agentic Sonnet model so far and the new default model for Free and Pro Claude users.

The pitch is clear: Sonnet 5 brings a lot of the agentic work that recently required Opus-class models into a cheaper, faster, broadly available tier. It can plan, use browsers and terminals, handle long coding tasks, and run with adaptive thinking by default.

For Claude Code users, that makes Sonnet 5 more important than a normal model refresh. It is likely to become the default execution layer for many teams: not the strongest model Anthropic offers, but the one developers will reach for most often.

The upgrade is not frictionless. Sonnet 5 has a new tokenizer, different API behavior around thinking and sampling parameters, real-time cyber safeguards, and a pricing story that is cheaper per token than Opus but not always cheaper per task.

Anthropic has just announced the release of Claude Sonnet 4.5, marking a significant milestone in AI development. This latest iteration represents what Anthropic calls "the best coding model in the world" with substantial improvements across reasoning, mathematics, computer use, and safety alignment. For developers using Claude Code, this release brings unprecedented capabilities that will transform how we approach complex programming tasks.

What Makes Claude Sonnet 4.5 Special?​

Claude Sonnet 4.5 isn't just an incremental update—it's a fundamental leap forward in AI model capabilities, particularly designed with developers in mind.