SeoSignal - On-Page SEO Checker & Auditor

One-click on-page SEO audit: title, meta, headings, Open Graph, schema, images, links and SERP preview. Private, in your browser.

SeoSignal is a fast, on-page SEO checker and website auditor that scores any web page in one click and shows you exactly what to fix. Meta tags, headings, canonical and robots directives, structured data (schema), Core Web Vitals, links, images, and accessibility - all analyzed instantly, right in your browser. No sign-up. No API keys. No data leaves your device. Just open a page and click. ━━━━━━━━━━━━━━━━━━━━━━ WHAT YOU GET FOR FREE ━━━━━━━━━━━━━━━━━━━━━━ • 0-100 SEO score with category breakdowns (Meta, Content, Technical, Social, Accessibility) and a prioritized list of issues to fix first • 50+ on-page checks: title & meta description (with pixel-width preview), H1-H6 structure, canonical, robots / X-Robots-Tag, robots.txt rules, hreflang and validity, HTTPS & mixed content, text compression, DOM size, language and charset • HTTP status & indexability: detects 4xx/5xx, redirects, and noindex pages so you never optimize a page that cannot rank • Structured data (JSON-LD) validation with rich-result readiness for 24 schema types • Core Web Vitals measured live: LCP, CLS, INP, FCP and TTFB, with the responsible element and clear fixes • Google SERP preview + social preview cards for Facebook, X (Twitter), LinkedIn and WhatsApp • Image audit: missing alt text, missing dimensions (CLS), modern format (WebP/AVIF) and oversized images • Link analysis: internal vs external, dofollow/nofollow, and anchor-text quality • Keyword density (1/2/3-word), focus-keyword placement and readability • HTTP response & security headers panel, robots.txt and sitemap.xml shortcuts • "Since last scan" tracking to see your score improve over time • Full-page report view + copy to Markdown • 48-language interface, light/dark/auto theme ━━━━━━━━━━━━━━━━━━━━━━ PREMIUM (7-day free trial) ━━━━━━━━━━━━━━━━━━━━━━ • Whole-site crawl (10 / 50 / 100 / entire site): per-page scores plus site-wide issues - broken internal links (with source pages), redirect chains, orphan pages, sitemap audit, hreflang reciprocity and near-duplicate content • On-page broken / 404 link checking (real HTTP status of every link) • Two-page side-by-side compare to benchmark against any competitor URL • Branded client reports (single page AND whole site) - export to PDF, CSV and JSON with your agency name and logo • Content ideas from real Google searches for your primary keyword ━━━━━━━━━━━━━━━━━━━━━━ WHY SEOSIGNAL ━━━━━━━━━━━━━━━━━━━━━━ • 100% on-device - your pages and data are never uploaded to us or any third party • No tracking, no analytics, no data selling • No account, no login, works the moment you install it • Built for real workflows: agencies, SEO specialists, content teams, developers and site owners • Works on Chrome, Edge, Opera and Firefox ━━━━━━━━━━━━━━━━━━━━━━ PERFECT FOR ━━━━━━━━━━━━━━━━━━━━━━ • SEO specialists running quick on-page audits • Agencies delivering branded client reports • Content and editorial teams checking pages before publishing • Developers validating meta tags, schema and Core Web Vitals • Site owners who want to rank higher without a steep learning curve ━━━━━━━━━━━━━━━━━━━━━━ PRIVACY ━━━━━━━━━━━━━━━━━━━━━━ SeoSignal analyzes pages entirely on your device. Page content is read only to compute your SEO score and is never sent to our servers. Network requests go only to the site you are auditing (to read HTTP status, headers and robots.txt), to Google (only if you use Content ideas), and to our payment provider for license validation. See our privacy policy for full details. Install SeoSignal and turn any page into an actionable SEO checklist in seconds.