100% Free

    Free Website Tools

    Check your site's security, performance, SEO, and DNS configuration. Instant results, no signup required.

    Need to audit a list of sites?

    Try our bulk checkers — run up to 25 URLs in one paste with CSV export.

    Bulk tools

    SSL Checker

    Check if your SSL/TLS certificate is valid, properly configured, and when it expires. Get instant results for any URL.

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    Security Headers

    Scan your website's HTTP security headers and get a grade from A+ to F. Find missing headers and get configuration examples.

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    DNS Lookup

    View all DNS records for any domain — A, AAAA, CNAME, MX, TXT, NS records. Verify DNS configuration instantly.

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    Meta Tags

    Extract and validate meta tags from any URL — title, description, Open Graph, Twitter Cards, and more.

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    Carbon Calculator

    Estimate the CO₂ emissions of any web page. See how your site compares to others and get tips to reduce your carbon footprint.

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    Mixed Content

    Find HTTP resources loaded on HTTPS pages. Mixed content breaks the padlock icon and creates security warnings.

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    Email Auth

    Validate your domain's email authentication records. Check SPF, DKIM, and DMARC configuration to improve email deliverability.

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    Core Web Vitals

    Test LCP, INP, and CLS for any URL. Get the same Lighthouse-grade scores Google uses to rank your pages.

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    Mobile-Friendly

    Check if Google sees your page as mobile-friendly. Find viewport, tap target, and font-size issues that hurt mobile rankings.

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    Observatory Scan

    Get a full A+ to F security grade for any site. Tests headers, cookies, mixed content, and Subresource Integrity.

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    PWA Readiness

    Check if your site qualifies as an installable Progressive Web App. Tests manifest, service worker, icons, and offline support.

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    Image Optimization

    Find oversized, uncompressed, or wrong-format images on any page. Get exact byte savings for WebP/AVIF conversion.

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    Lazy Loading

    Find images and iframes that should be lazy-loaded. See how many requests you can defer below the fold.

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    Font Loading

    Audit how your web fonts load. Find FOIT, missing `font-display: swap`, and oversized font files dragging down LCP and CLS.

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    Third-Party Scripts

    Find every third-party script on your page. Measure bytes, blocking time, and which ones are killing INP.

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    Broken Links

    Crawl your site and find every 404, 5xx, redirect chain, and dead external link. See exact URLs, source pages, and HTTP status codes.

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    Exposed Services

    See which ports and services your domain exposes to the public internet. Spot critical risks like open SSH, MySQL, Redis, or RDP before attackers do.

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    Indexability

    Check whether Google can actually index your page. Detects noindex, canonical conflicts, X-Robots-Tag headers, soft 404s, and crawl blockers.

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    Content Freshness

    Find which pages on your site haven't been updated in months. See last-modified dates, age in days, and which pages need a refresh to keep ranking.

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    Sitemap Checker

    Validate your XML sitemap. Find it, parse it, count URLs, detect sitemap indexes, and flag suspicious or broken sub-sitemaps.

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    Cert Transparency

    See every TLS certificate ever issued for your domain. Discover hidden subdomains, spot rogue certificates, and audit your CAs.

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    URL → Markdown

    Convert any web page to clean, LLM-ready Markdown. Strip ads, scripts, and chrome. Perfect for feeding pages to ChatGPT, Claude, or training data.

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    HTML Validator

    Validate any URL against the W3C HTML5 spec. Find every parser error, stray tag, duplicate ID, and accessibility-blocking issue in seconds.

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    RSS Validator

    Find every RSS and Atom feed on a page, verify the XML is valid, and count items. Critical for blogs, podcasts, newsletters, and AI-search syndication.

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    OG Comparison

    Compare Open Graph and Twitter Card metadata between any two URLs. See og:image previews, sizes, titles, descriptions, and canonical mismatches side-by-side.

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    Sitemap Diff

    Compare two XML sitemaps. See exactly which URLs were added, removed, or are common to both. Perfect for monitoring deploys, migrations, and competitor changes.

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    WordPress Detector

    Detect if a site runs WordPress. Identify the WordPress version, active theme, and visible plugins from the public HTML — no login required.

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    Hosting Detector

    Find out which hosting provider, CDN, and web server power any website. Identifies AWS, Cloudflare, Vercel, Netlify, Shopify, WP Engine, and 50+ other providers.

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    Uptime Checker

    Check if any website is up right now. Get HTTP status code, response time, full redirect chain, server header, and content size in seconds.

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    Malware Checker

    Check any site for malware, phishing and unwanted software using the Google Safe Browsing list. Instant result, no signup.

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    Cookie Compliance

    Detect whether a site has a cookie consent banner, identify the consent tool used, and check if tracking scripts load before consent (GDPR violation).

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    Privacy Policy Check

    Verify that a site has a Privacy Policy, Terms of Service, Cookie Policy, and Imprint. Detects missing legal pages — a hard requirement under GDPR, CCPA, and most jurisdictions.

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    Print Stylesheet

    Check if a page has print-specific CSS. Missing print styles mean broken layouts, wasted ink, and unprofessional output when users print or save as PDF.

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    Money Page Finder

    Auto-detect the most revenue-critical pages on any website. Surfaces pricing, signup, checkout, demo, and contact pages from the sitemap — the ones that must never go down.

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    Free SEO Audit

    Run a complete free SEO audit in under 60 seconds. Covers Core Web Vitals, on-page SEO, security, indexability, broken links, and mobile-friendliness — with deep-dive links to fix every issue.

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    llms.txt Generator

    Generate a spec-compliant llms.txt file in 30 seconds. Help ChatGPT, Claude, Perplexity, and other AI systems understand your site so they cite it correctly.

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    Bulk SSL Checker

    Check SSL certificates on up to 25 domains at once. Validity, expiry, issuer, TLS version and grade — exportable to CSV.

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    Bulk Headers

    Scan HTTP security headers across up to 25 URLs in one batch. HSTS, CSP, X-Frame-Options, Permissions-Policy — graded A+ to F.

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    Bulk DNS Lookup

    Resolve DNS records for up to 25 domains at once. A, AAAA, MX, NS, TXT, CNAME — exported as CSV for diff and audit.

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    Bulk Meta Tags

    Audit titles, meta descriptions, Open Graph and Twitter cards across up to 25 URLs in one paste. Spot duplicates and missing tags fast.

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    Bulk Mobile Test

    Check mobile-friendliness across up to 25 URLs at once. Viewport, tap targets, text size, content fit — pass/fail per URL.

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    Bulk PageSpeed

    Run PageSpeed (Lighthouse) on up to 25 URLs in one go. Performance score, LCP, CLS, and TBT per URL — exportable.

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    Bulk Uptime

    Check whether up to 25 sites are currently online. Status code, response time, and a per-URL up/down verdict.

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    Bulk Mixed Content

    Find HTTP resources loaded on HTTPS pages across up to 25 URLs. One paste to catch insecure images, scripts, and iframes at scale.

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    Bulk Broken Links

    Scan up to 25 pages for broken outbound links in one batch. Per-page count of 404s, 500s, and unreachable URLs.

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    Bulk Malware

    Cross-check up to 25 URLs against malware and phishing blocklists in one paste. Flag any site flagged by major safe-browsing sources.

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    Favicon Checker

    Check whether your site exposes a valid favicon at /favicon.ico and via <link rel="icon"> — and that browsers, search engines, and bookmark tools can actually fetch it.

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    Schema Checker

    Validate JSON-LD, Microdata, and RDFa structured data on any URL. See exactly which schema types are declared and whether they parse correctly for Google rich results.

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    WP Vulnerability Scanner

    Detect whether a site runs WordPress, identify the core version, and surface known CVEs against that release. Non-invasive — only reads what the site publicly exposes.

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    robots.txt Generator

    Build a spec-compliant robots.txt in 30 seconds. Block crawlers, allow specific paths, point search engines to your sitemap, and decide which AI crawlers can train on your site.

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    SPF Generator

    Build a valid SPF TXT record by ticking the email providers you use. Counts DNS lookups so you stay within the RFC 7208 limit of 10.

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    DMARC Generator

    Build a valid DMARC TXT record in under a minute. Choose your policy, set reporting addresses, and get a copy-paste record to publish at _dmarc.

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    Email Deliverability

    One-click audit of MX, SPF, DMARC, MTA-STS, and BIMI for any domain. Identifies the exact reason your mail is hitting spam — and what to fix first.

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    robots.txt Tester

    Fetch any site's robots.txt and audit it against the spec. Catches Disallow: /, missing sitemaps, broken syntax, oversized files, and unknown directives in one pass.

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    Hreflang Checker

    Scan any URL for hreflang tags and validate them against the spec. Catches missing self-references, missing x-default, invalid language codes, duplicate targets, and protocol mismatches.

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    Canonical Checker

    Check the canonical URL of any page. Finds missing, conflicting, relative, and cross-domain canonical tags — the quiet reason good pages drop out of the index.

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    Domain Age

    Look up when a domain was first registered, when it expires, and who it is registered with — straight from live RDAP registry data.

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    HTTP Status Code Reference

    Learn about every HTTP response code — what they mean, common causes, and how to fix them:

    Free Tools FAQ

    Common questions about our free website tools

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