TL;DR: I wrote one detailed prompt, gave the exact same prompt to ChatGPT Codex and Claude Code in VS Code, and let each build a shop website in one shot. No planning step, no follow-up fixes to the design. Codex finished first but its preview didn't open at first. Claude took longer and gave me a more interactive site with more images. I liked Claude's version more, so I'm continuing with it.
A website from an agency or freelancer can easily cost hundreds or thousands of euros. I wanted to see how far one prompt gets you today, with no coding and no designer. Not a finished production site, just the base: layout, design system, components and structure that I can later turn into a real shop.
The rule was one-shot prompting. One prompt in, look at what comes out. Of course a working shop needs tweaking after that, but the point was to compare the raw first output.
Why WordPress? I'm in Estonia, and local shipping methods usually exist as WordPress plugins (or on platforms that have been around long enough). So whatever the AI builds has to be something I can move into WordPress later.
There are lots of website prompts shared online. One I found was made with Gemini 3.1 Pro and the site it produced looked really good. The prompt itself was the impressive part: very specific, very detailed.
I didn't want a copy of that website. So I pasted that prompt into Gemini as an example and told it to learn how the prompt is written, not to reuse it. I only have Gemini 3, not 3.1 Pro, but for writing a prompt that didn't matter.
Then I described what I actually needed: a base for a website selling four battery garden tools, modern, easy to understand, clean, but professional.
Gemini came back with a full prompt: a high-end, "creative technology" direction with core design rules, typography, components and the rest. That became the single prompt for both agents.
In VS Code I created a new project folder for Claude and told it, roughly: build me a new website from the prompt I'm about to give you, it has to be usable as a WordPress site later, and I want a preview. Then I pasted the Gemini prompt.
For Codex I did exactly the same with a second folder. Only the file location changed. One thing I normally do with Claude is hit the plan button first, so it lays out what it's going to build and I can say yes or no to parts. This time I skipped it on purpose. I already had a detailed prompt, and I wanted a true one-shot comparison.
A small UX difference while they worked: Codex streams all its text right in the panel. With Claude Code you click into the step to see what it's doing.
Codex finished first. Clicking the website did nothing at first: the preview didn't work. Codex then added Python, I told it to run it, and the preview came up. The hero line was "The future is silent power without fumes", with spots for products and some descriptions underneath. Clean and decent.
Claude Code was still writing a lot of files when Codex finished. When it was done it told me which file to open. At first glance it looked very similar to the Codex site, but the buttons had a nice movement on them, there were more images and more sections overall.
Then I put them side by side, Codex on the left, Claude on the right.
| ChatGPT Codex | Claude Code | |
|---|---|---|
| Prompt | Same one-shot prompt | Same one-shot prompt |
| Finished | First | Later, still writing when Codex was done |
| Preview | Didn't open at first; worked after it added Python and I told it to run | Told me which file to open, opened fine |
| Button movement | Different style | More interactive |
| Images | Fewer | More |
| Product view | Placeholder spots plus descriptions | Different layout and style |
| Bottom of the page | Different content | Different content, more stuff overall |
| My pick | ✅ |
The honest summary: both are a usable base from one prompt. The texture, style and product view are different between the two. Claude's felt more "wow", more interactive and nicer overall. That's my taste, though; you might prefer the Codex one when you see them.
I'm continuing with Claude. The next step is building an actual website with an actual product that can really run on WordPress.
Written up from my video with AI help; the test and the opinions are mine.
Full run on video (my channel): https://www.youtube.com/watch?v=AR-A7Ro1te4