Free · Runs in Claude Code

Claude SEO Checker

Audit and fix your site’s technical SEO right in your codebase — a free, AI-powered SEO checker and analysis tool built on Claude Code. No crawler, no hosted dashboard, no signup.

/plugin marketplace add clauderegistry/marketplace
/plugin install seo-optimizer@clauderegistry
/seo-audit ./src

Powered by the seo-optimizer plugin.

What the Claude SEO Checker checks

A comprehensive technical SEO audit across ten categories, scored 0–100 with every issue ranked by impact.

Title tags & meta descriptions

Presence, length (50–60 / 120–155 chars), uniqueness, and keyword relevance.

Viewport & charset

Mobile-first viewport and an early UTF-8 charset declaration.

Open Graph tags

og:title, description, image, url, and type for rich social sharing.

Twitter Cards

summary_large_image cards with title, description, and image.

Heading hierarchy

Exactly one H1, no skipped levels, semantic structure.

Image SEO

Descriptive alt text and explicit width/height to protect CLS.

Links

Descriptive anchors, rel="noopener", and crawlable navigation.

robots.txt & sitemap.xml

Crawlability, sitemap reference, and valid XML.

Canonical URLs

Self-referencing, absolute, HTTPS canonicals that match og:url.

Structured data

Schema.org JSON-LD (Article, FAQ, Breadcrumb, Organization…).

How it works

1

Install

Add the marketplace and the seo-optimizer plugin to Claude Code.

2

Audit

Run /seo-audit on a file, a directory, or your framework’s layout. You get a scored report with critical, error, and warning findings.

3

Fix

Apply precise fixes with /seo-optimize (or conservative micro-edits with /seo-reviewer), or ask the SEO Expert skill.

Why a Claude-native SEO checker

Claude SEO CheckerLighthouseAhrefs / Semrush
Audits your source codeYesNo (rendered page)No (crawls live site)
Fixes issues for youYesNoNo
Works before you deployYesNoNo
Free, no signupYesYesNo
Framework-awareYesPartialNo

Frequently asked questions

What is the Claude SEO Checker?

It is a free, AI-powered SEO audit tool that runs inside Claude Code. You install the seo-optimizer plugin and run /seo-audit to scan any HTML file, React, Next.js, or Vue app, or static site for the technical SEO issues that hurt rankings — then fix them with /seo-optimize.

Is it free?

Yes. The seo-optimizer plugin is free and open source (MIT). There is no signup, subscription, or hosted dashboard — it runs locally in Claude Code on your own machine.

What does the SEO checker check?

Title tags and meta descriptions, viewport and charset, Open Graph and Twitter Card tags, heading hierarchy, image alt text, internal and external links, robots.txt and sitemap.xml, canonical URLs, and Schema.org structured data — scored 0–100 and prioritized by impact.

How is it different from Ahrefs, Semrush, or Screaming Frog?

Traditional tools crawl your live, rendered site and hand you a report to act on. The Claude SEO Checker reads your source code (framework layouts, components, templates), catches issues before you deploy, and can apply the fixes for you with /seo-optimize instead of just flagging them.

Does it work with Next.js, React, Vue, or Astro?

Yes. It is framework-aware and detects React (Create React App, Next.js), Vue (Nuxt), Angular, Svelte (SvelteKit), static site generators (Gatsby, Eleventy, Hugo, Astro), WordPress themes, and plain HTML.

Can it fix SEO issues automatically?

Yes. After the audit, /seo-optimize applies precise, minimal edits (and /seo-reviewer applies conservative micro-edits under a 5% change limit), so you get fixes as a diff you can review — not a to-do list.

Do I need to deploy my site to check it?

No. Because it runs on your source files, you can audit and fix SEO in a feature branch before anything ships — no live URL or deployment required.

Run your first SEO audit

Install the seo-optimizer plugin and run /seo-audit on your project.

View the plugin