ChatGPT Just Got Seriously Good at Building Websites — Here's What Changed

Ask ChatGPT to build a landing page in mid-2024 and you got something forgettable. Ask it today and the output is a different category entirely. Here's an honest breakdown of the model upgrades — from GPT-4.1 to GPT-5.4 — that got us here, what OpenAI trained for specifically, and what it means for businesses thinking about their next website.