Guides / How to build

How to Build a Website with AI: From First Prompt to Live Site

How to build a website with AI: plan the pages, write a first prompt that works, fix the copy and mobile layout, handle SEO, and publish on your own domain.

Mythex Team · 2026-09-29 · 8 min read

To build a website with AI, write down what the site is for and which pages it needs, describe that to an AI website or app builder in a few plain sentences, and let it generate a first version you can see in a live preview. Then fix the copy, check it on a phone, add the basics search engines need, and publish it to a domain. Most small sites — a business site, a portfolio, a landing page, a simple blog — can go from idea to live in a single sitting.

What kind of website are you building?

"Website" covers very different things, and the kind you pick changes what you ask for:

If yours is in the last row, you are really building a web app with a marketing front. That is fine — AI app builders handle both — but plan the app part separately; our guide on how to build an app with AI covers it.

AI website builders vs. templates vs. AI app builders

There are three common routes, and each one suits someone different.

• Template-based builders with AI features (Wix, Squarespace, Framer and similar). You start from a designed template and edit visually; AI helps write text or suggest a layout. They are good when you want a proven design, a visual editor, and built-in extras such as a blog or appointment widget.
• AI app builders (Mythex, Lovable, Bolt and others). You describe the site in chat and the AI writes the code from scratch, then runs it in a live preview. They are good when you want something tailored, want to change it by talking rather than dragging boxes, or expect to add app features later.
• Hand-built or agency sites. Still the right call for large sites with complex content workflows, strict brand systems or legal review on every page.

For a side-by-side look at specific tools, see the best AI website builders.

Step 1: Plan the site on one page

Before you open any tool, answer these five questions. It takes ten minutes and saves hours of back-and-forth:

1. Who is the visitor, and what should they do? "Local homeowners who should call for a quote" is a plan. "Everyone" is not.
2. Which pages exist? List them. Most small sites need four or five.
3. What goes on each page? A line or two each: "Services: three services with a short description and a starting price."
4. What is real? Gather your actual business name, services, prices, address, opening hours, photos and testimonials you are allowed to use. The AI will invent placeholders for anything you don't give it.
5. How should it feel? Two or three words ("calm, clean, lots of white space") or a link to a site you like.

Step 2: Write the first prompt

A good first prompt describes the business and the pages, not the code:

Build a website for Harbor Physio, a physiotherapy clinic in a small coastal town. Pages: Home (hero with "Book an assessment" button, three reasons to choose us, short testimonials section), Services (sports injury, back pain, post-surgery rehab — each with a paragraph and session length), About (the two physiotherapists, with placeholders for photos), and Contact (address, opening hours, phone, and a contact form). Calm, clean look with a soft blue accent. Mobile-first. Use real-sounding copy, no lorem ipsum, and don't invent reviews or awards.

That last sentence matters. AI tools are happy to fill empty space with made-up testimonials, "trusted by 10,000 customers" banners or fake awards. Tell it not to, and check anyway.

If you already have a logo, brand colours or a screenshot of a site you like, attach it. For more patterns, see how to write prompts for AI app builders.

Step 3: Review it like a visitor

When the first version appears, don't start by tweaking fonts. Walk through it as your visitor would:

• Can you tell what the business does within five seconds of landing?
• Is the main button obvious, and does it go somewhere?
• Does every page in the menu exist and link correctly?
• Switch to a phone-sized view. Most visitors will arrive on a phone, and that is where cramped text and oversized images show up.

Then change one thing at a time. "Make the hero headline shorter and put the phone number in the header" gets a better result than "make it better". If a change goes wrong, roll back to an earlier version rather than trying to talk your way out of it.

Step 4: Replace placeholders with real content

The first draft will have placeholder images and generic sentences. Work page by page:

• Copy. Paste your real service descriptions, prices and hours. Ask the AI to tighten them, but keep the facts yours.
• Images. Upload your own photos where you can. Stock photos are fine for backgrounds; real photos of your work, team or premises build more trust.
• Proof. Only use testimonials, logos and numbers you can back up.
• Legal pages. If you collect any personal data through a form, you will usually need a privacy policy. Ask the AI for a page, then have it checked against the rules where you operate — a generated policy is a starting point, not legal advice.

Step 5: Forms, bookings and other "app" parts

A contact form needs somewhere to send submissions. The options, from simplest to most involved:

If you need real bookings or payments, see how to build a booking app and how to add payments to your app.

Step 6: SEO basics before you share it

An AI can write a beautiful page that search engines barely understand. Before launch, ask for:

• A unique title and meta description on every page
• One clear main heading per page, with sensible subheadings
• Descriptive alt text on images
• Open Graph tags, so links look right when shared on social media or in messages
• A sitemap and robots file

One technical point is worth knowing. Many AI builders produce single-page apps, where the browser builds the page with JavaScript. Search engines can index these, but static or server-rendered HTML is more dependable for pages that need to rank. If search traffic matters, ask for a static site or a framework that renders pages on the server. Our guide to SEO for AI-built websites goes deeper.

Step 7: Publish and connect a domain

Publishing turns the preview into a public site. Most builders give you a free subdomain first, which is fine for testing and sharing with friends. For a business, connect your own domain: you either buy one through the builder or point a domain you already own at the site with a DNS record. How to connect a custom domain walks through the DNS part.

After launch, set up a free Google Search Console account so you can see whether your pages are being indexed.

Common mistakes

• Asking for everything at once. Twelve pages, a blog, a shop and a members area in one prompt produces a shallow version of each. Build the core pages first.
• Publishing placeholder text. Search every page for "Lorem", "Your Company" and made-up numbers before going live.
• Ignoring mobile. Check every page at phone width, not just the home page.
• Leaving the call to action vague. Every page should make the next step obvious: call, book, buy or get in touch.
• Forgetting who will update it. If someone else will edit the site weekly, make sure they can — either by chatting with the same builder, or by choosing a tool with a visual editor.

What it costs

A simple site built with AI usually costs far less than a designed-and-built one. The running costs to plan for are:

• The builder. Most have a free tier for trying things and a paid plan for custom domains and more usage.
• Hosting. Sometimes included in the plan, sometimes usage-based.
• A domain name. A yearly registration fee, which depends on the name and ending.
• Extras. An email provider for form notifications, or paid tools for bookings or newsletters.

When a website builder is the better choice

Be honest about what you need. If you want a classic brochure site, a visual editor for a non-technical colleague, a built-in blog with scheduling, or an online shop with inventory and shipping handled for you, a template-based website builder or a dedicated platform like Shopify may serve you better than any AI-generated code. AI app builders pull ahead when the site is unusual, changes often, or is the front door to something that behaves like an app.

Building it with Mythex

Mythex is an AI app builder, and websites are one of the most common things people build with it. You describe the site, it builds it in a live preview (including a phone-size view), and you publish to a yourname.mythex.ai address; on Pro you can buy a domain in Mythex or connect one you own. If search rankings matter, you can ask for a plain static site rather than the default React app — see the docs on static websites and SEO for your published app.

Mythex is not a CMS: there is no separate editor login for a marketing team, so changes are made by chatting with the builder or editing the code. To skip the blank page, start from one of the website templates or portfolio templates, each of which opens a new project with a starter prompt filled in.