| Product | Astro |
| Website | astro.build |
| Category | Web Framework / Static Site Generator |
| Pricing | Free and open source |
What Is Astro?
Astro is a web framework that ships zero JavaScript by default. You write components using React, Vue, Svelte, or Astro’s own syntax, and Astro renders them to static HTML at build time. JavaScript is only sent to the browser when a component needs interactivity — and only the JavaScript for that specific component, not the entire framework.
This approach is called “Islands Architecture.” The page is static HTML (the ocean), and interactive components are islands of JavaScript within it. A blog post with a static article body and an interactive comment section sends JavaScript only for the comment section.
Key Features
Zero JavaScript by Default
Build a page with React components, and the browser receives HTML. No React runtime, no hydration, no JavaScript bundle. The page loads instantly because there’s nothing to download, parse, or execute. Only components marked with client:load, client:visible, or client:idle send JavaScript.
Framework Agnostic
Use React, Vue, Svelte, Solid, or Preact components in the same project. Mix frameworks on the same page if needed. Astro renders all of them to static HTML. This means you can use the best component library for each part of your site without committing to a single framework.
Content Collections
Organize Markdown, MDX, and data files into typed content collections. Astro validates the frontmatter with Zod schemas, generates type-safe APIs for querying content, and renders Markdown to HTML. This is the best developer experience for content-heavy sites: blogs, documentation, marketing pages.
View Transitions
Astro’s view transitions add smooth page-to-page animations with a single directive. Pages slide, fade, or morph between each other without a full page reload. The result feels like a SPA but is still static HTML with no client-side router.
Who Is This For?
- Content-heavy websites (blogs, docs, marketing sites) that need to be fast
- Developers who use React/Vue/Svelte but want faster page loads
- SEO-focused sites that need excellent Core Web Vitals
- Anyone building static or mostly-static websites
Pros
- Zero JavaScript by default (fastest possible page load)
- Use any framework (React, Vue, Svelte, Solid)
- Content collections with type safety
- View transitions for SPA-like feel
- Excellent for SEO and Core Web Vitals
- Growing ecosystem of integrations
Cons
- Not for app-heavy SPAs (use Next.js or SvelteKit)
- Islands model limits component communication
- Smaller community than Next.js
- Server-side rendering is newer and less battle-tested
- Some learning curve for island hydration directives
Verdict
Astro is the best framework for content-heavy websites. The zero-JavaScript-by-default approach means your pages load as fast as physically possible. Content collections give you the best developer experience for working with Markdown and data. And the framework-agnostic approach means you’re not locked into a single component library.
The boundary is clear: if your site is mostly content with some interactive components, Astro is the best choice. If your site is mostly interactive with some content, use Next.js, SvelteKit, or a SPA framework instead. Astro is excellent at what it does because it doesn’t try to do everything.
Build a web framework or developer tool?
Get reviewed and linked from our 27-site network.
See Packages