Free SEO Audit Tool

Free SEO Audit Tool — Real Google Lighthouse Data for Your Website

Our free SEO audit tool runs a complete analysis of any URL using Google PageSpeed Insights (Lighthouse v12) — the exact same engine Google uses to evaluate websites for search rankings. Enter any URL and get a comprehensive report covering your SEO score, Core Web Vitals, performance opportunities, accessibility issues, and best practice violations across both mobile and desktop. No signup, no daily limits, no mock data. Every result is fetched live from Google's servers in real time.

What Google Lighthouse Checks and Why It Matters for Rankings

Google Lighthouse is the audit engine that powers Google's Core Web Vitals measurements — the ranking signals Google officially announced in 2021 that directly affect page experience scores in search results. Lighthouse audits four categories: Performance (how fast your page loads), SEO (how well search engines can crawl and understand your content), Accessibility (how usable your site is for everyone), and Best Practices (security and modern web standards). Each category produces a score from 0 to 100. Scores above 90 are green, 50-89 are yellow, and below 50 are red. Our tool runs Lighthouse on both mobile and desktop simultaneously and displays all results in a structured, actionable report.

Core Web Vitals — The Three Metrics That Directly Affect Rankings

Google's Core Web Vitals are three specific performance metrics that form part of the Page Experience signal used in search ranking. Largest Contentful Paint (LCP) measures loading performance — how quickly the main content appears. Google's threshold is under 2.5 seconds for good. Cumulative Layout Shift (CLS) measures visual stability — how much the page unexpectedly shifts during loading. Under 0.1 is good. Total Blocking Time (TBT), which correlates with First Input Delay (FID) and Interaction to Next Paint (INP), measures interactivity — how quickly the page responds to user actions. Under 200ms is good. Our audit tool shows all three with real user field data (where available from Chrome User Experience Report) alongside lab data from the simulated Lighthouse test, giving you both views.

SEO Checks — What On-Page Signals Google Evaluates

The SEO audit section checks the technical on-page signals that search engine crawlers use to understand your content. A missing title tag, absent meta description, or blocked robots.txt can prevent a page from ranking entirely regardless of content quality. Canonical tags prevent duplicate content penalties when multiple URLs serve similar content. Viewport meta tags ensure mobile usability. Structured data (JSON-LD schema markup) enables rich results in Google Search. Our SEO tab checks all of these and flags any issues with a clear pass, warning, or fail status and a description of how to fix it. Use our free Schema Markup Generator to add structured data to pages that are missing it.

Performance Opportunities — Specific Fixes with Estimated Savings

The performance tab shows actionable opportunities with estimated time and byte savings for each fix. Common opportunities include eliminating render-blocking JavaScript and CSS (which delays FCP), removing unused JavaScript (often the largest opportunity on plugin-heavy WordPress sites), compressing images and converting to WebP format, enabling text compression (Gzip or Brotli), implementing proper caching, and reducing server response time. Each opportunity links to detailed documentation on how to fix it. Unlike tools that only show a score, our tool gives you the specific files and URLs causing the issues, so you know exactly what to change.

Mobile vs Desktop — Why Mobile Score Is More Important

Google uses mobile-first indexing for all websites since 2023 — this means Google primarily uses the mobile version of your content for indexing and ranking. Your mobile Lighthouse score is therefore the more important of the two. It is normal for mobile scores to be 20-40 points lower than desktop because the mobile audit simulates a Moto G4 device on a slow 4G network with CPU throttling applied. If your mobile performance score is below 50, it is a strong signal that your site may be delivering a poor experience to mobile users, which Google penalizes in rankings. Use the device toggle to compare your mobile and desktop results side by side.

Accessibility Audits — Why They Matter for Both Users and SEO

Accessibility and SEO are deeply interconnected. Many accessibility improvements — proper heading hierarchy, descriptive image alt text, meaningful link text, sufficient color contrast — also help search engines understand your content structure and meaning. Image alt text serves both screen readers and Google Image Search. Semantic HTML heading structure (H1 → H2 → H3) helps both users with assistive technology and Google's content understanding algorithms. A Lighthouse accessibility score below 70 often indicates structural problems that hurt both user experience and SEO simultaneously.

How Often to Run an SEO Audit

For actively managed websites, run an SEO audit after every significant change: after publishing new content, after installing or updating plugins, after theme changes, after adding third-party scripts, or after any performance optimization work. A sudden drop in your SEO or performance score between audits pinpoints exactly when and what caused the regression. For minimal-change sites, a monthly audit establishes a health baseline. The most common cause of unexpected performance drops is a new third-party script (analytics, chat widgets, ad systems) added without performance review. After completing an audit and fixing issues, also update your meta descriptions using our free Meta Description Generator and validate your page schema using our Schema Markup Generator.