KeyDen: Keyword Density Checker & SEO Analyzer

Free keyword density checker & SEO analyzer. N-gram analysis (1-4 words), density %, highlighting. 100% local.

KeyDen is a free keyword density checker and SEO analyzer tool built right into your browser. Instantly analyze any web page or selected text to find keyword density percentage, spot overused phrases, and optimize your content for search engines. HOW TO USE: - Click the KeyDen icon in the toolbar to analyze the current page - Right-click any page and choose "KeyDen — Keyword density" - Press Alt+K for instant keyword density analysis - Select text first to analyze only that selection KEYWORD DENSITY ANALYZER: KeyDen performs deep n-gram analysis with 1-word, 2-word, 3-word, and 4-word phrases. The keyword density formula is simple: (keyword count / total words) x 100%. KeyDen applies this keyword density formula automatically and displays the keyword density percentage for every phrase found on the page. SEO ANALYZER FEATURES: - Keyword density checker tool with color-coded results: red (over-optimized, >3%), amber (optimal zone, 1.5-3%), green (safe, <1.5%) - See how much keyword density is good for SEO at a glance with visual indicators - Page title and meta description included in the analysis - Total word count displayed in the header - Hidden content and image alt text analysis (optional toggles) SMART FILTERING: - Built-in stop word filtering (170+ English stop words) to focus on meaningful keywords - Toggle stop words, hidden content, and image alt text with instant results - Pre-computed analysis for all filter combinations — switching is instant, no re-analysis needed KEYWORD HIGHLIGHTING: - Keywords from red and amber zones are automatically highlighted on the page with colored markers and count badges - Click any keyword row in the table to highlight just that specific keyword on the page - Visual badges show count and density right on the page SIDEBAR INTERFACE: - 4 tab cards (1-Word, 2-Word, 3-Word, 4-Word) showing max density and unique keyword count - Sortable table by keyword name, count, or density - Copy all results to clipboard in TSV format for spreadsheet use SELECTION MODE: - Select any text on the page, then activate KeyDen to analyze only that selection - Perfect for checking keyword density in specific sections, paragraphs, or competitor content KEYWORD DENSITY IN SEO: Understanding keyword density meaning is essential for on-page SEO. KeyDen is a keyword density analyzer that helps you maintain optimal keyword density for SEO without over-stuffing. The keyword density calculator shows exact percentages so you always know where you stand. PRIVACY FIRST: KeyDen is a 100% local keyword density tool. No data is ever sent to any server. No analytics, no tracking, no accounts. Everything runs in your browser. This is a truly free keyword density checker with zero data collection. Unlike online keyword density tools, KeyDen works as a browser extension — no need to copy-paste text into external websites. It is a keyword density extension that works on any page, instantly, with one click. KEYBOARD SHORTCUT: Alt+K — instantly open the keyword density analyzer on the current page. Developed by ElectricBlaze https://electricblaze.com/