What Is Astro? A Plain-English Explanation

Astro is a free tool that makes websites. You write pages. Astro turns them into a finished site. You copy that site to a host, and it’s online.

It’s best for sites people read: blogs, personal sites, small business sites, and guides like this one.

What makes Astro different

Most modern web tools send a lot of JavaScript to every visitor. That’s the code that makes pages move. The visitor’s browser has to load it all before the page feels ready. On an old phone, that wait is real.

Astro does the opposite. It sends plain pages, and adds JavaScript only to the small parts that need it. So Astro sites load fast, even on slow phones.

What are islands?

Picture a page as a calm sea of plain text and pictures. Now and then you need a part that does something, like a search box. That part is an island. It gets its own bit of JavaScript. Everything around it stays simple.

You can build islands with popular tools like React, Vue and Svelte. Most beginner sites don’t need any. Our guide to Astro islands explains it with a real example.

What can you build with it?

• A blog
• A personal site, or a portfolio of your work
• A small business site
• A set of instructions or a manual
• A landing page for one product

Astro can also run code on a server, for things like logins. But if your site is really an app, like a dashboard, a tool made for apps may suit you better. See Astro vs Next.js.

Is it right for you?

Astro suits you if:

• You want a fast site that you fully own.
• You’re happy to type a few short lines in a terminal. Part 4 of Start from zero shows you how.
• You’d like to learn how websites really work.

A hosted site builder suits you better if you never want to see a line of code. That’s a fine choice too.

Still not sure? Take our two-minute check, or compare in Astro vs WordPress.

What about EmDash?

You may hear about EmDash, Cloudflare’s free content system. It’s built on Astro and adds a dashboard, so you can write and edit in your browser. We explain it in what is EmDash.

Where to start

Never built a site before? Read Start from zero first. It’s six short pages. Then the free course builds a real site with you, in about two hours.

Frequently asked questions

Is Astro free?

Yes. Astro is free, and it stays free even for a business site. It's open source, which means anyone can read and improve the code.

Who owns Astro?

The company that makes Astro joined Cloudflare in January 2026. Cloudflare says Astro will stay free and open source.

Is Astro a website builder like Wix?

No. With Wix you drag boxes around in a browser. With Astro you work with files on your computer. It's a little more to learn, and you get a faster site that you fully own.