Which AI model is best for coding? A hands-on comparison (flaviocopes.com)

Claude Opus 5.5 has emerged as the leading AI model for coding as of September 23, 2026, according to Cursor's latest coding leaderboard. Opus 5.5 outperforms its predecessor, being faster and more cost-effective while successfully passing hidden tests in three out of four attempts during evaluations. Closely following it is GPT-5.6 Sol, which excels in tasks requiring precise, well-defined adjustments while using fewer tokens. Both models demonstrate significant potential across various coding tasks, with GPT-6 Sol recently introduced as an upcoming contender to watch. This comparison is crucial for the AI/ML community, emphasizing the importance of model suitability for specific tasks rather than solely relying on leaderboard rankings. The findings show that while Opus 5.5 is ideal for general coding tasks, specialized models like GPT-5.6 Sol and Claude Fable 5.1 can outperform it in scenarios demanding accuracy and complex reasoning. Technical details revealed include pricing structures and API availability for various models, with the new models offering diverse capabilities, making it essential for developers to choose the right model based on their specific needs and budget constraints.