The best AI for building websites is the one that ships a site that works, not just one that photographs well. So we built the same website four times, once per model, from one prompt and with no fixes, and then clicked through every control the brief asked for. All four passed. What separates them is how far each went beyond the checklist, and what that cost in time.
Did every AI-built website actually work?
Yes. In all four builds the monthly-to-yearly switch rewrote the plan prices, Pro from $12 to $10 and Studio from $29 to $24, with the yearly totals of $120 and $288 underneath. All four have a working FAQ and a menu button that opens on a phone. None logged a runtime error during our scripted recording, and each is a single HTML file between 64 KB and 132 KB that opens straight from disk.
What did each model add that nobody asked for?
This is where the models differ, and it is a fair proxy for how they will treat your project.
- Claude Opus 5.5 put a full booking widget in the hero and added a sign-up dialog with a "check your inbox" step. It also announces the price change to screen readers.
- Claude Fable 5.1 animated a scripted cursor that picks a slot and pays $180 inside the hero, looping every ten seconds.
- GPT-6 Astra added a sign-up dialog and a week picker you can page through.
- GPT-6.1 Sol added an interactive booking dialog where you choose a session type and time and get a confirmation.
How long did each one take?
Between 9 and 43 minutes. The two GPT models finished in about ten minutes each; Fable took 28 and Opus 43. The table below is pulled from the run logs, not estimated.
| Model | Finished | Wall time | Output tokens | Files | Source size | Runtime errors | API-equivalent cost | Attempts |
|---|---|---|---|---|---|---|---|---|
| Claude Opus 5.5 | Yes | 43m 20s | 144k | 1 | 132 KB | 0 | $7.15 | 1 |
| Claude Fable 5.1 | Yes | 28m 14s | 131k | 1 | 92 KB | 0 | $10.88 | 1 |
| GPT-6 Astra | Yes | 9m 58s | 34k | 1 | 64 KB | 0 | $2.88 | 1 |
| GPT-6.1 Sol | Yes | 9m 08s | 45k | 1 | 73 KB | 0 | $0.69 | 1 |
Which one should you use to build a website?
Pick Claude Opus 5.5 when the site is the product and you want the most finished first draft: it did the most, and the extra half hour shows. Pick GPT-6.1 Sol when you want a working base fast and cheaply, because at its list prices of $2 and $10 per million input and output tokens (OpenAI) the whole build came to $0.69, against $7.15 for Opus. I would not pick GPT-6 Astra for this job: it charges five times Sol's price and produced a near-twin of Sol's page, down to the same two fonts, DM Sans and Instrument Serif.
One caution applies to all four. The sign-up and booking dialogs are front-end demonstrations; nothing is sent anywhere, because the brief forbade network requests. A model builds the website. It does not yet build the business behind it.
Judge them before you read the labels: four sites, names hidden, pick the one you would launch.
Take the blind testWhat should you check before you trust an AI-built site?
Run the same three checks we did, in the live build, not in the recording. Click every switch and confirm the numbers change everywhere, not just in the headline. Open the page at phone width and use the menu. Then read the footer and the FAQ, because filler copy hides at the bottom of a page. The methodology lists every control our recorder exercises, so you can repeat it on any model you are considering.
Frequently asked questions
What is the best AI for building a website in 2026?
On our landing-page brief all four models shipped a complete, working single-file site. Claude Opus 5.5 built the most functional one, GPT-6.1 Sol built a solid one in nine minutes for the lowest token cost, and the choice between them is mostly about whether you value depth or speed.
Did the AI-built websites actually work, or only look right?
They worked. In every build the monthly-to-yearly switch changed the plan prices from $12 and $29 to $10 and $24, the FAQ opened and closed, and the phone menu toggled. Three of the four also added a working sign-up or booking dialog the brief did not ask for.
Can I put one of these websites live?
Technically yes, because each one is a single HTML file that opens from disk and can be dropped onto any static host. Practically, the forms are demonstrations with no backend, so sign-ups and bookings would need a real service behind them first.
Is a website builder like Wix better than a coding model?
They solve different problems. A builder gives you hosting, editing and forms out of the box; a coding model gives you a custom file you own and must host yourself. If you want to change every pixel and keep the code, a model is the better start.