GoSEO – On-Page SEO Checker

SEO checker: meta tags, keyword density, headings, images, links, schema markup, and Core Web Vitals. Private on-page SEO audit tool

GoSEO checks on-page SEO instantly. See meta tags, keywords, headings, images, links, schema, and Core Web Vitals for any page. No logins, no ads, no tracking. Everything runs locally in your browser. 🔧 At a Glance ✓ Meta tags, SERP preview, Open Graph & Twitter cards ✓ Keywords, word counts, density analysis ✓ H1–H6 heading structure ✓ Image analysis (ALT text, size, format) ✓ Link checker (internal/external, nofollow, missing titles) ✓ Script tags & resource hints ✓ JSON-LD structured data viewer ✓ Core Web Vitals (LCP, CLS, FCP, TTFB) ✓ Export data (CSV / ZIP) ✓ Light & dark themes ✅ Instant Overview SERP & social previews - See how your page appears in Google, Facebook, and Twitter Essential meta tags - Title, description, canonical, robots, hreflang, favicon with character counts Core Web Vitals - LCP, CLS, FCP, TTFB metrics for performance tracking Scripts & resources - All script tags and resource hints (preload, preconnect, dns-prefetch) Indexability signals - Quick checks for robots.txt and sitemap references ✅ Keywords & Word Analysis Word count, unique words, reading time, text/HTML ratio Single words and up to 5-word phrases Sort by word, count, or density Real-time search with minimum count filter Density chart to spot under or over-optimized keywords Export keyword data to CSV ✅ Headings Full H1–H6 structure in a clean hierarchy Spot missing H1s, duplicates, or skipped levels Click any heading to jump to it on the page Export all headings (Text/CSV) ✅ Images See every image on the page Spot missing ALT text, missing dimensions, oversized files, and outdated formats Check file size, dimensions, format, and lazy-loading status Filter to show only images needing attention Export the full list to CSV or download all images as a ZIP ✅ Links View total links, unique URLs, internal/external breakdown, nofollow tags, missing titles Broken link detection runs automatically in the background Filter by type (internal, external, nofollow, broken) Click any link to jump to it on the page Export all link data to CSV ✅ Structured Data (Schema) View all JSON-LD structured data blocks on the page See parsed and raw JSON Export all schemas as JSON 🎯 Built For ✓ SEO consultants doing quick client audits ✓ Content writers optimizing articles ✓ Web developers checking technical implementation ✓ Marketers reviewing landing pages and competitors ✓ Anyone tired of juggling multiple SEO tools 🛡️ Privacy Everything runs in your browser. No tracking, no data collection, no external requests. 🧑‍💻 Open Source Fully open source (MIT license). Code is public and transparent on GitHub.