Free tools to check a website

Ten shorter paths for one specific question. The same engine as the full audit with fewer distractions — no login, no email address, and any domain, including one you do not own.

Single-signal tests

Each of these runs the same scan as the full audit but reports on one scoring pillar. If you want the whole picture, start with the full audit and get all eight at once.

• Page speed and Core Web Vitals — LCP, INP, CLS, TTFB, resource weight, caching and compression, with field and lab kept apart.
• Security headers and SSL — CSP, HSTS, X-Frame-Options, certificate validity, TLS version, mixed content and cookie flags.
• Mobile-friendly test — Viewport tag, pinch-zoom, responsive CSS, and page weight and speed on a phone.
• Accessibility test — Image alt text, form labels, document structure and automated axe-core violations.
• Hosting and DNS checker — Nameservers, A and AAAA records, CDN fingerprints, DNSSEC, CAA, HTTP/3 and real availability.
• Email authentication test — Find out whether anyone can send mail impersonating your domain, and exactly what to publish to stop it.
• AI readiness test — Whether ChatGPT, Claude and Perplexity can read your site — and whether you are letting them.

Comparison and overview tools

These three do not examine one signal; they put results side by side — yours against a competitor's, or against a whole industry.

• SEO comparison — two sites side by side — Put your domain against a competitor's: eight pillars and Core Web Vitals in parallel, with a shareable link.
• Is this website safe? — Domain reputation in phishing and malware feeds, domain age, impersonation of known brands, and certificate status.
• SEO rankings by industry — The average score in your category and the sites leading it — the context a single score cannot give you.

Why separate pages instead of one button

Because the questions differ. Someone checking why their email lands in spam does not need a Core Web Vitals chart at that moment — they need an answer about SPF and DMARC, with a record they can paste. Each of these tools reads the same scan data but shows only the part you came for, explained in the context of one problem. The complete result is always one click away.

Frequently asked questions

Are the tools genuinely free? Yes. None of them requires an account, an email address or a card. Scans are rate-limited so the service survives automated traffic, but they are not limited by payment.

How do they differ from the full audit? Not at all in measurement — they run the same scan and the same rules. The difference is presentation: a tool shows one pillar with commentary focused on that problem, while the full audit shows all eight with a combined score and a repair order.

Can I check somebody else's website? Yes. Every test runs from the outside on publicly available data: the server's response, the served HTML and public DNS. None requires proof of domain ownership, because none reaches for anything an ordinary visitor cannot see.

How long does a scan take? Usually one to three minutes, depending on the size of the site and whether external data such as a PageSpeed measurement is available. The result opens at its own address, which you can keep or pass on.