ChatGPT vs Claude vs Codex for Building Client Websites: What We Tested

ChatGPT vs Claude for building websites is the wrong fight if you build sites for local businesses. Both can write a clean one-page site. What decides the job is the setup around the model. Can it open the business's own website? Can it save the photos and the page as files? Can it draft an email to the owner? Claude Code and Codex can do all three on your own computer. ChatGPT now has its own website feature too, but we have not run our prompt there. Below is what we tested, what we did not, and how to choose.

What a client website job asks of an AI

A one-page sample site for a plumber or a diner is not hard code. It is a list of small chores done in the right order:

1. Open the business's own website and its Google listing.
2. Copy the true facts: name, phone, address, hours, services.
3. Save a few real photos from the business's own site.
4. Write one HTML page that works on a phone.
5. Check the page against a list.
6. Write a short email to the owner and save it as a draft.

Any good model can do step 4. Steps 1, 3 and 6 need tools. The model has to browse, write files and reach your email. So the real question is which product gives the model those hands.

Here is how the three line up, from their own documentation as read on October 21, 2026.

Plans and limits change often. Check the current plan pages for Claude and ChatGPT before you pay for anything.

What we actually tested

SiteRevive writes a prompt for each list of businesses. You paste it into your own AI. The AI builds one sample site per business from that business's own public facts and photos, then drafts a short email. Claude is the AI we test that prompt with. In October 2026 we also ran it in Codex on New Jersey leads, to see how a second agent handles the same job.

Codex, run 1: four businesses

The first run had 4 New Jersey businesses. Codex built 4 local sample sites and wrote 4 email drafts. It sent nothing and published nothing.

Three of the four businesses had fewer than 3 usable photos on their own sites. Codex did not fill the gap with stock or made-up images. It gave those three a design with no photos. That is the behavior you want. A sample that shows someone else's kitchen is worse than one with no kitchen at all.

Codex, run 2: 33 businesses in one prompt

The second run had 33 businesses in a single prompt. Here is the count, SiteRevive data, October 2026:

Two lines in that table matter more than the rest.

The 3 skips are honest failures. When a business website refused the download, Codex stopped and said so. It did not guess.

The 30 "maps not checked" flags mean a person still has to open each Google Maps listing and confirm it is the same business at the same address before any email goes out. The agent did the heavy work. The final check stayed human.

Claude: the one we test with

Our prompt is written and tested against Claude first. One example: a sample restaurant site, built with Claude Code from the restaurant's own public photos, as a pitch. We do not name the restaurant, because it is not a customer. The photos were its own food and dining room, taken from its own website, and the page was never published.

ChatGPT: not tested by us

We have not run SiteRevive's prompt in ChatGPT for this article, so we will not rate it. What we can say comes from OpenAI's own pages. Codex now lives inside the ChatGPT family, with a desktop app, a CLI, an IDE extension and a cloud version. OpenAI's help center also describes Sites, a public beta that builds a website from a prompt and gives you a private preview. Treat those as OpenAI's claims until you test them on your own job.

How to choose for client work

My opinion, after 15 years running a marketing agency: pick the tool whose weak spot you can live with. Then build a checking habit around it.

Pick Claude Code if

• You want the tool our prompt is tested with.
• You are fine with a desktop app or a terminal window.
• You want the agent to read the business's site, save photos, write the page and check it in one pass.

Anthropic's docs describe Claude Code as a tool that reads files, edits them, runs commands and works with your other tools. Most ways to use it need a paid Claude plan. If you are deciding between Claude plans, see Claude Pro or Max for building websites.

Pick Codex if

• You already pay for ChatGPT and want an agent that works on your own files.
• You want a second agent to compare against.

OpenAI's Codex CLI page says it can inspect files, make edits and run the tools on your machine. Live web search is something you switch on for a run. Remember that, because the job needs the web.

Pick ChatGPT chat or Sites if

• You want to draft page copy, research a trade, or try a quick hosted page.
• You are not yet building pages for many businesses at once.

The tradeoff: a site hosted inside someone else's product may not be the file you want to hand to a client later. Ask where the file lives and how you move it to the owner's own domain. Our guide to handing over a website to a client covers the move.

Tradeoffs nobody puts in the headline

The parts that matter more than the model

Across our runs, the same three things decided quality. None of them was the brand of the model.

First, the prompt. A vague prompt makes every model invent details. A strict one tells it to leave a gap empty instead of guessing. Our guide to a prompt to build a website with AI gives you a clean template you can paste into any of these tools.

Second, the photos. Real photos from the business's own site beat any generated image for a pitch, because the owner recognises them. We explain why in real photos vs AI images on small business websites.

Third, the check. In our run, the agent passed its own 22-point list on 30 sites. A person still had to confirm 30 Maps listings. Plan for that time.

If you want the full path from first lead to first site, start with how to start a website agency with AI. For a Claude-only walkthrough, see build websites with Claude for clients. And if you are weighing a drag-and-drop builder instead, read AI website builder for agencies.

Where SiteRevive fits

SiteRevive does the part before the AI. It finds local U.S. businesses with old or missing websites. It checks each site and writes down the real problems. It keeps an email only when it finds one on the business's own website. Then it writes the prompt for your AI. Your AI builds the sample site and drafts the email, from your own email account. SiteRevive's servers never send email.

It does not promise replies, calls or sales. Plans start at $97 a month, with a 7-day money-back guarantee, no questions asked. You can see the three plans on the SiteRevive pricing page.

A short test you can run this week

You do not need to trust our table. Run your own.

1. Pick one real local business with an old website.
2. Paste the same prompt into two tools.
3. Open both pages on your phone.
4. Count the facts on each page you can confirm on the business's own site.
5. Count the facts you cannot confirm. Each one is a problem.
6. Read both email drafts out loud. Keep the one you would send under your own name.

The tool with fewer invented facts wins. In my experience that matters more to an owner than a nicer font.

For the full counts from the 33-business Codex run and a review list for your own batch, read Codex for building websites.