Claude Sonnet 5 is here
Claude Sonnet 5 has been released, according to an announcement.
Background
- This tweet announces the release of "Claude Sonnet 5," a new version of Anthropic's Claude AI model family. Sonnet sits between the smaller Haiku and larger Opus models in Anthropic's tiered naming.
- The tweet is satirical/fictional — it appears to be from the "Claude Devs" parody account, not from Anthropic. As of mid-2025, Claude Sonnet 4 is the latest publicly available version.
- The joke plays on the rapid pace of AI model releases and the social media hype cycle where each new model is treated as a world-changing breakthrough, even when improvements are incremental.