All Tools 48+
Free, instant, no signup. Check any website for SEO, performance, security, DNS, SSL, and more.
Site Analysis
HTTP headers, security, speed, redirects, broken links
- HTTP Headers Response headers, status codes, redirects
- Advanced Custom method, headers, POST body, timeout
- Health Score Comprehensive audit: SEO, perf, security
- PageSpeed Core Web Vitals, LCP, CLS, TTFB
- Security HSTS, CSP, X-Frame-Options, CORS
- SEO Audit Full SEO check by Google, Yandex, Bing, AI
- Redirect Chain Full redirect chain with status codes
- Broken Links Find 404 and error links on any page
- HTTP/2 & HTTP/3 Check HTTP/2, HTTP/3, ALPN support
- HAR Analyzer Analyze .har files from DevTools
- HTTP Status Code Checker HTTP status codes reference
- HTTP Compare HTTP-level response comparison
Domain & DNS
DNS records, propagation, WHOIS, SSL, subdomains
- DNS A, AAAA, MX, TXT, NS, CNAME, SOA
- DNS Propagation DNS spread across 15+ global resolvers
- MX Lookup Mail server records for a domain
- WHOIS Domain registrar, creation, expiry dates
- Subdomains Find all subdomains via CT logs
- Reverse IP Find all domains on the same IP
- CMS Detector Detect CMS, framework, CDN, WAF
- Tech Stack Detector Wappalyzer: 7500+ technologies
- Screenshot Take a screenshot of any page
Network
Ping, traceroute, IP, ports, ASN, latency
Security
Cookies, CSP, CORS, malware, DNSBL, AbuseIPDB, RKN
- SSL Certificate validity, expiry, ciphers
- CSP Content-Security-Policy parser
- CORS Access-Control-Allow-Origin/Methods
- Cookie HttpOnly, Secure, SameSite flags
- Mixed Content Find HTTP resources on HTTPS pages
- Malware VirusTotal, Google Safe Browsing
- Spam Lists Check IP/domain in 20+ spam blacklists
- IP Abuse Check Abuse confidence score, report count
- RKN Check Check if blocked by Russian regulator
SPF, DKIM, DMARC, SMTP relay, Open Graph
SEO & AI
SEO audit, schema, keywords, robots.txt, AI-readiness, llms.txt, carbon
- Schema Checker Validate JSON-LD, Microdata, Open Graph
- OG Preview Open Graph & Twitter Card preview
- Keywords Meta tags, keyword density
- Robots.txt Validate and analyze robots.txt
- Site Comparison Compare two sites side by side
- AI Readiness Check accessibility for AI crawlers
- llms.txt Validate or generate llms.txt
- Carbon CO2 per pageview, green hosting
Utilities
Formatter, JWT, cron tester, TTL/uptime calculators, batch checks
- Formatter JSON, XML, HTML, Base64, MD5, SHA, Punycode
- JWT Decoder Decode header & payload, check expiry
- Cron Tester Validate cron expression, next runs
- TTL Calculator Convert TTL seconds, look up DNS TTL
- IP/CIDR Calculator Subnet, broadcast, host range, mask
- Uptime / SLA Calculator 99.9% = X minutes of downtime per year
- Downtime Cost Calculate business loss from downtime
- Batch Check up to 50 URLs at once
- Heartbeat Cron job & script monitoring