Anthropic's free Claude 4 Sonnet aced my coding tests - but its paid Opus model somehow didn't

Anthropic / ZDNET The pace of AI improvement fascinates me. What sucked a year ago is at the top of the heap this year. I saw that over the past few months, as both Google's Gemini and Microsoft's Copilot went from the bottom rung on the AI coding ladder to the winner's circle, passing all of my coding tests. Also: How I test an AI chatbot's coding ability - and you can, too Today, another language model is making the trek up the ladder. What makes this interesting is that the underdog player is moving into the winner's circle, where the odds-on favorite only climbed up a rung or two before getting stuck. Like most LLM offerings, Anthropic offers its Claude chatbot in both free and paid versions. The free version now available is Claude 4 Sonnet. The paid version, which comes with its $20/month Pro plan, is Claude 4 Opus. Opus is also available to those using Anthropic's even more expensive Max plan. The model is the same, but there are fewer limits. Also: The best AI for coding i ... Read full article.