YAN SEO

Advanced Technical SEO audit and on-page analysis tool.

YAN SEO — Advanced Technical SEO Audit Tool for Chrome STOP guessing. START ranking. YAN SEO is a powerful Chrome extension that performs a full on-page and technical SEO audit of any website — instantly, right from your browser's side panel. No external tools, no subscriptions, no data sent anywhere. Just open a page, click the icon, and get a complete professional-grade analysis in seconds. 🔍 What YAN SEO Does: ----------------------------------------- All 21 Modules in Detail: 1. Meta & Structure Analysis Analyzes the Title Tag and Meta Description with: Real-time character counters with visual progress bars Defined optimal ranges: title 30–60 chars, description 120–160 chars Status indicator: green (optimal), yellow (too short), red (too long/missing) Detects when fields are completely absent from the HTML 2. SERP Preview Simulator Simulates how the page will appear in Google search results: Desktop and mobile toggle — each with different truncation limits (60/55 chars title, 160/120 chars description) Google-style URL breadcrumbs (domain › category › subcategory) Visual truncation warnings with exceeded character count Simulated Rich Snippets based on detected schema: FAQ: shows first 2 question/answer pairs Product: price + star rating Article/BlogPosting: author + publish date HowTo: numbered steps with names Breadcrumb: full navigation trail LocalBusiness: address + phone + rating Recipe: cook time + yield Review/AggregateRating: stars with review count 3. Content Metrics Full statistics about the page's main content area: Word counter with intelligent main content detection (ignores navigation, sidebars, footers) Estimated reading time (words ÷ 225 wpm) Evaluation badge: ⚠️ Thin content (< 300 words) ✅ Acceptable (300–800 words) 🏆 Pillar content (> 800 words) Extracts only visible text (excludes scripts, styles, iframes, CSS-hidden elements) 4. Readability Score Measures text complexity using the Flesch-Kincaid algorithm: Formula: 206.835 − 1.015 × (words/sentences) − 84.6 × (syllables/words) 0–100 scale: 0 = very difficult (academic), 100 = very easy (elementary) Displays: score, equivalent school grade level, sentence count, average words per sentence, paragraph count Color-coded: green (easy), yellow (medium), red (highly technical/difficult) 5. Keyword Density Analysis When you enter a target keyword: Counts exact occurrences (case-insensitive) in visible text Calculates density: (occurrences / total words) × 100 Density status: green (< 0.5% = low), yellow (0.5–2.5% = optimal), red (> 2.5% = keyword stuffing) Verifies presence in the title tag and in the H1 Click on the result → highlights and scrolls to the first occurrence on the page 6. Top Keywords / N-Grams Automatic extraction of the most repeated words and phrases: Analyzes 1-grams through 7-grams (single words up to 7-word phrases) Removes stop words in English and Spanish (43+ words) Shows Top 15 for each n-gram size with frequency count Interface with n-gram selector and clickable keyword tags Click on a phrase → searches and highlights it on the page in real time 7. Heading Hierarchy Audits the H1–H6 heading structure: Validates that there is exactly 1 H1 (more than 1 = error) Detects level jumps (e.g., H1→H3 without an H2 in between = critical error) Shows a visual indented tree of the full heading hierarchy Each heading is clickable → scrolls to that element on the page Count by level (H1: 1, H2: 5, H3: 8, etc.) Red error indicators on problematic elements 8. Image Analysis Complete audit of all images on the page: Detects lazy-loaded images by checking multiple attributes: data-src, data-lazy-src, data-original, data-lazy, data-url, srcset Excludes tracking pixels (images < 5px) For each image shows: thumbnail, filename, alt and title status Status badges: ✅ (has alt), ❌ (missing alt), ⚠️ (no title) Filters by status: all / missing alt / missing title Click on thumbnail → scrolls to that image on the page "View Original" link to open image in a new tab 9. Link Checker Concurrent link checker with a pool of 3 simultaneous workers: Classifies each link as: ✅ Valid (200), ↪ Redirect (3xx), ⚠️ Slow (8s timeout), ❌ Broken (4xx/5xx), ⚠️ CORS blocked, ⚠️ Rate-limited (429) Tries HEAD first, falls back to GET if it fails (405/403) Real-time progress bar + counter Filter by category (valid, redirects, warnings, invalid) Export results as CSV or copy URLs to clipboard per category Analyzes only content links (excludes navigation menus, wp-admin links) 10. Schema Markup Detection Detection and visualization of structured data: Parses all <script type="application/ld+json"> tags on the page Recursively extracts types (including nested @graph structures) Icons per type: 🛒 Product, 🔗 Breadcrumb, ❓ FAQ, 📰 Article, etc. Expandable accordion with the full JSON of each schema Complete list of all detected types Integrated with SERP preview to simulate real rich snippets 11. Hreflang Tags Audit of international SEO tags: Detects all <link rel="alternate" hreflang="..."> tags in the head Table showing language code + target URL Validates correct language code format 12. Open Graph / Social Preview Simulates how the page will look when shared on social networks: Renders a preview card styled like Facebook/LinkedIn with the real og:image Shows og:title, og:description, domain Badges indicating whether OG values match or differ from the SEO meta tags 13. Core Web Vitals Real performance metrics using the browser's Performance Observer API: LCP (Largest Contentful Paint): which element took longest to render + description + size INP (Interaction to Next Paint): user interaction response time (98th percentile) CLS (Cumulative Layout Shift): visual stability score + layout shift sources FCP (First Contentful Paint): first pixel rendered on screen TTFB (Time to First Byte): server response time TBT (Total Blocking Time): sum of long tasks (> 50ms) blocking the main thread Count of render-blocking resources (synchronous JS/CSS) List of the 5 heaviest resources with size in KB DOM node count (> 1500 = warning) Color-coded thresholds: 🟢 Good, 🟡 Needs Improvement, 🔴 Poor 14. AI Content Fingerprint Detects signals of AI-generated content: TTR (Type-Token Ratio): vocabulary diversity — AI tends to repeat words Sentence length standard deviation: AI produces very uniform sentence lengths 30+ AI phrases detected: "it is worth noting", "moreover", "comprehensive guide", "delve into", "it is important to", etc. Entity density: proper nouns, years, numeric values (AI generates fewer) First-person usage: % of "I/we/my/our" (humans use more) Data density: numbers, percentages, measurements (signal of human expertise) Final scale 5–95 with labels: "Mostly Human" (≤25), "Natural" (≤45), "Neutral" (≤60), "AI Signals" (≤75), "AI-like" (>75) Gauge visualization + list of detected problematic phrases 15. Competitor Gap Radar Visual comparison against any competitor page: Enter a competitor URL → the extension fetches it via the service worker (cross-origin) Automatically extracts: title, description, word count, H1–H3 count, images, schemas, internal links, meta score Generates an SVG radar chart with 6 axes: Content, Headings, Images, Schemas, Internal Links, Meta Score Two overlaid polygons: you (blue) vs. competitor (red) Axis-by-axis comparison grid with numeric values Win/loss summary: "You win X out of 6 categories" Smart normalization: content ÷ 2000, headings ÷ 20, images ÷ 15, schemas ÷ 5, links ÷ 50 16. Internal Link Architecture Map of the internal linking structure: Page depth: how many levels deep the current URL is (/blog/seo/tips = level 3) Internal and external link totals with count of unique external domains Top anchors: the 6 most used anchor texts with frequency Path categories: most linked URL patterns (/blog, /products, etc.) with distribution bars Deep links: links pointing to pages more than 2 levels deep Orphan risk: alert if the current page is > 2 levels deep with fewer than 5 internal links pointing to it 17. Page Intent Classifier Automatically classifies the page's search intent: 4 detected types: 🛒 Transactional (buy, download, subscribe), 🔍 Commercial (compare, best, reviews), ℹ️ Informational (how, what, guide, tutorial), 🧭 Navigational (home, login) Scoring system based on text patterns, UI elements (CTA buttons, prices, forms), and keyword presence in the title Shows primary intent with percentage and secondary intent if it exceeds 10% Percentage bars for all 4 intents Detected trigger tags (e.g., "buy now in title", "visible price", "how-to question") 18. SEO Counter / Text Optimizer Built-in SEO writing tool: Text field with live character and word counter Validation for title (≤ 65 chars = ✅ green, > 65 = ❌ red) and description (70–155 chars = ✅) Text case conversion buttons: UPPERCASE, Title Case, lowercase Useful for drafting and optimizing titles and descriptions before publishing 19. Markdown Export Converts the page content to clean Markdown: Recursive DOM traversal: h1–h6 → #, bold → **, italic → *, links → [text](url), images →  Strips: scripts, styles, nav, footer, aside Auto-generates frontmatter (title, description, URL, og:image) Shows compression metrics: original HTML size vs. Markdown size, noise reduction %, context multiplier for AI usage Buttons to copy to clipboard or download as .md file Ideal for feeding AI models (ChatGPT, Claude) with clean page content 20. Root Files Checker Verifies essential technical files at the domain root: Sitemap XML: intelligent multi-path search (/sitemap.xml, /sitemap_index.xml, /wp-sitemap.xml) and also parses robots.txt looking for Sitemap: directives robots.txt: verifies existence and accessibility llms.txt: checks presence of the new standard for AI crawlers Uses HEAD→GET fallback with 7-second timeout, treats 429 as "found" 21. Technical SEO Checklist 8-point technical checklist with pass/fail indicators: H1: exactly 1 present on the page SSL: HTTPS protocol active Indexability: absence of noindex in meta robots Language: lang attribute defined in <html> Mobile Viewport: width=device-width in meta viewport Charset: UTF-8 encoding declared Nofollow: detection of global nofollow in meta robots Nosnippet: detection of nosnippet in meta robots Cross-Cutting Features: ------------------ Feature Detail: SEO Score (0–100) 11-factor weighted algorithm: title (15pts), description (15pts), URL (8pts), H1 (10pts), content volume (10pts), image alt text (8pts), technical checks (12pts), canonical (5pts), schema (7pts), internal links (5pts), readability (5pts) Context Banner Top bar showing page H1, HTTPS status, indexability, language, and canonical — always visible Drag & Drop All modules are reorderable by dragging, order saved to localStorage Interactive Scroll Click headings, links, or images → auto-scroll to that element on the page with visual highlight Auto-analysis Launches automatically on tab change or URL change No external data All analysis runs 100% in the browser — no data leaves your machine