SEO Checker Tool

On-page SEO audit for the current tab: title, meta, headings, images, links, schema, Open Graph. Runs 100% locally.

SEO Checker Tool gives you an instant, on-page SEO audit of any webpage in a single click — no signup, no account, no data leaving your browser. Click the toolbar icon on any page and get a 0–100 SEO score plus a clear breakdown of what's passing, what's a warning, and what's broken. Designed for SEOs, content writers, marketers, web developers, and site owners who want a fast sanity check without opening a heavyweight web tool. WHAT IT CHECKS • Title tag — presence and length (30–60 char sweet spot) • Meta description — presence and length (70–160 chars) • Headings — H1 count, full H1–H6 outline, empty headings • Canonical URL, robots meta, hreflang, viewport, charset, language • Images — missing alt, empty alt, missing lazy-load, oversized • Links — internal vs external, nofollow, links without anchor text, unsafe target="_blank" without rel="noopener" • Open Graph and Twitter Card tags • Schema markup — JSON-LD and microdata types detected • Content — word count, paragraphs, top keywords by density • Technical — HTTPS, DOCTYPE, HTML size, scripts, stylesheets, iframes, favicon, web manifest, Apple touch icon FEATURES • Instant 0–100 weighted score with pass / warning / issue counts • 8 organized tabs: Overview, Meta, Headings, Content, Links, Images, Social, Tech • Light, Dark, and Auto (system) themes • Compact and expanded popup sizes • Export full report as JSON • Copy a clean text summary to clipboard • Works on any standard https:// or http:// page PRIVACY-FIRST • 100% local — analysis runs entirely inside your browser • No data is sent to any server, ever • No account, no login, no telemetry, no cookies, no analytics • No tracking of your browsing history • Only two permissions: activeTab and scripting (so it can read the page you click on) • No host permissions, no <all_urls> • No remote code, no inline scripts — strict Content Security Policy LIMITATIONS • Cannot analyze browser-internal pages (chrome://, edge://, about:, chrome-extension://) — open a regular website instead • Some pages with strict CSPs may block content scripts • Analyzes the current rendered DOM (so JavaScript-rendered content is included) Want a deeper, multi-page crawl with backlinks, Core Web Vitals, and historical tracking? Try the Pro web version at https://seochecktool.com Open source, no ads, no upsells inside the extension itself. Built by Empro IT Solutions.