Anthropic says Claude Opus 4 is its most powerful model and the best coding model in the world, while Sonnet 4 is replacing Sonnet 3.7 in the chatbot.

Anthropic has unveiled Claude 4, the latest generation of its AI models. The company boasts that the new Claude Opus 4 and Claude Sonnet 4 models are at the top of the game for AI assistants with unmatched coding skills and the ability to function independently for long periods of time.

Claude 4 Sonnet is a leaner model, with improvements built on Anthropic's Claude 3.7 Sonnet model. The 3.7 model often had problems with overeagerness and sometimes did more than the user asked it to do, Amodei said. While it's a less resource-intensive model, it still performs well, he said.