ASTRO SEO AUDIT · ISLAND HYDRATION · STATIC OUTPUT · AI VISIBILITY
Free Astro SEO Audit
Astro's island architecture is great for performance — but client:only components, hybrid output gaps, and missing Content Collections metadata create SEO blind spots that a generic tool won't find. DeepSEOAnalysis audits Astro sites with framework-specific context.
WHAT WE CHECK
6 Astro-specific SEO checks
Beyond the 80+ general checks, the engine applies Astro-aware analysis when it detects an Astro-built site.
Output mode and crawlability
Astro supports three output modes: static (fully pre-rendered HTML), server (SSR on every request), and hybrid (mix of both). Static and SSR are both crawlable, but hybrid builds can leave gaps if key pages are accidentally left as server-rendered behind a slow or auth-gated adapter. The audit verifies that all important pages deliver complete HTML in the first HTTP response.
JavaScript island hydration
Astro's island architecture is SEO-friendly when used correctly — but `client:only` directives skip server rendering entirely, producing an empty element in the initial HTML. The audit identifies any `client:only` islands that contain headings, body text, or internal links that crawlers need to see, and flags them as JS rendering gaps requiring a switch to `client:load` or server-side rendering.
Image component and LCP
Astro's built-in `<Image>` component automatically generates width, height, srcset, and next-gen format output — but only when used. Raw `<img>` tags bypass these optimisations. The audit checks the LCP element across your key pages: if it's an unsized `<img>` tag rather than Astro's Image component, it flags the specific element and estimates the LCP penalty from missing optimisations.
Sitemap plugin coverage
The `@astrojs/sitemap` integration auto-generates a sitemap, but only includes routes it can discover at build time. Dynamic routes using `getStaticPaths` are included; server-rendered routes are not. The audit cross-references the sitemap against all crawled pages to identify important pages missing from the sitemap — a common gap for Astro sites with hybrid rendering.
Content Collections metadata
Astro's Content Collections let you define a schema for frontmatter — including title, description, and OG image fields. Pages built from Collections that lack `description` in their schema (or use the schema but omit it per-entry) produce missing meta descriptions across all collection entries. The audit detects this pattern and flags the affected pages and the collection schema field that needs to be required.
AI visibility for Astro sites
Astro has no built-in support for llms.txt or FAQPage schema, but both are straightforward to add: llms.txt as a static file in `/public/`, and FAQPage JSON-LD via an Astro component with a `<script type="application/ld+json">` slot. The audit checks all five AI visibility signals and shows exactly which Astro patterns and component snippets to use for each.
HOW IT WORKS
Audit your Astro site in 60 seconds
- Enter your Astro site's URL. Works with Astro deployed to Vercel, Netlify, Cloudflare Pages, or any host — no build access needed.
- We crawl and analyse. The engine crawls up to 50 pages (free) or 1,000 pages (paid), checks for JS rendering gaps, validates sitemap coverage, measures Core Web Vitals, and evaluates AI visibility signals.
- You get a prioritised report. Framework-specific issues first (client:only gaps, hybrid output misses, missing schema), then general SEO — each with a concrete Astro-specific fix.
FAQ
Questions about the Astro SEO audit
Does DeepSEOAnalysis detect Astro-specific SEO issues?
Yes. The engine detects Astro signals — static output patterns, island hydration markers, and Astro-generated HTML structure — and surfaces Astro-specific guidance alongside the 80+ general checks.
Does Astro's static output guarantee good crawlability?
Static Astro (output: static) is the most crawlable configuration — all HTML is pre-rendered with no JavaScript dependency. But if you use output: server or output: hybrid for dynamic routes, those routes depend on your server adapter. The audit verifies that all key pages deliver full HTML in the initial response, with no critical content requiring JavaScript to render.
How does Astro's island architecture affect SEO?
Islands that use client:load or client:visible hydration deliver the component HTML as part of the initial SSR/SSG response — Googlebot can see this content immediately. Islands that use client:only="react" (or similar) skip server rendering entirely, producing an empty `<div>` in the initial HTML. The audit flags any client:only islands that contain content crawlers would need to see (headings, body text, internal links).
Is the Astro SEO audit free?
Yes. The full audit — crawlability, Core Web Vitals, structured data, AI visibility — is free with no signup and no email gate. Paid plans add saved history, scheduled monitoring, and agency workflows.