SEO Audit — Free On-Page Checker

Instantly audit any webpage for on-page SEO issues — right from your browser, with zero setup and zero data leaving your device. WHY THIS TOOL Most SEO checkers either dump a wall of raw data on you or require an account, a subscription, and your site's data flowing through someone else's servers before you see a single result. This extension runs entirely on your device. Click the icon, get a full audit in seconds, and nothing about the page you're checking is ever transmitted anywhere except where it needs to be — like checking a site's own sitemap.xml or robots.txt, which happens directly between your browser and that site. WHAT IT CHECKS Every audit runs 20+ checks across the areas that actually affect rankings: On-page fundamentals - Title tag — presence, length, and whether it's a duplicate of another page you've audited this session - Meta description — presence and ideal length (120–160 characters) - Canonical tag — presence, validity, and whether it's self-referencing - Robots meta directives — flags noindex/nofollow pages before they surprise you - Heading structure — H1 count, and whether your heading hierarchy skips levels Content quality - Word count — flags thin content that's unlikely to rank - Readability — Flesch-Kincaid grade-level scoring, so you know if your copy is harder to read than it needs to be - Title/H1 similarity — flags when they're identical, missing an opportunity to target different phrasing Images - Alt text coverage — flags missing, empty, or filename-like alt text ("IMG_1234.jpg" isn't helping anyone) - Image sizing — flags images being served much larger than they're displayed, a common cause of slow-loading pages Links - Internal linking — flags pages with too few internal links, which hurts crawlability and site structure - External links — flags likely affiliate/ad links missing proper rel="sponsored"/"nofollow" attribution - Broken internal links — actively checks your internal links and flags anything returning an error Technical SEO - Open Graph tags — checks all four core tags so your page looks right when shared on social media - Structured data — validates JSON-LD schema markup and flags parsing errors - Mixed content — flags insecure (http://) resources loading on an https:// page - Viewport meta tag — flags pages missing proper mobile configuration - HTML lang attribute, favicon, and URL structure — the smaller technical details that add up Site-level checks - sitemap.xml and robots.txt presence, checked directly against the site being audited - Page performance timing (TTFB, DOMContentLoaded, full load) TARGET KEYWORD CHECKING Enter a keyword you're targeting, and the extension checks whether it appears in your title, H1, and opening content — so you can confirm a page is actually optimized for the term you're trying to rank for. BUILT FOR REAL WORK, NOT JUST A SCORE Every issue comes with a clear explanation of why it matters, not just a red flag. Issues that affect multiple items — like images missing alt text — show you exactly which ones, so you can go fix them instead of hunting through your page source. Results are organized by severity (critical, warning, info) so you know what to fix first. 100% PRIVATE BY DESIGN - No account required - No login - No data collection - No tracking - All analysis happens locally in your browser - The only network requests made are between your browser and the site you're auditing (for sitemap/robots/link checks) — never to us WHO IT'S FOR Freelancers, agencies, and site owners who manage WordPress sites, Elementor builds, WooCommerce stores, or any web page and want a fast, honest read on its SEO health without signing up for another tool or handing over their data to get it. Full privacy policy: https://wptechmaster.com/seo-toolkit-privacy-policy/