🔍 Website Check Tools
A suite of tools that audit your website — security, SEO, LLMO, structured data, DNS, SSL certificates, and more — with just a URL or hostname.
✅ 100% free, no signup. All requests are made server-side from DevLab.
Composite Checks
Individual Checks
Security Check
HTTPS / HSTS / CSP / XFO / Mixed Content
HTTP Headers
All response headers with explanations
DNS Records
A / AAAA / CNAME / MX / TXT / SPF / DMARC
Structured Data
Extract JSON-LD, microdata, Schema.org
Basic SEO Check
title / description / OG / canonical / image alt
SSL / Certificate
Issuer / validity / SAN / chain
CAA Records
issue / issuewild / iodef + parent inheritance
robots.txt Analyzer
User-agent / Allow / Disallow / Sitemap
Open Graph Validator
og:* / Twitter Card / image reachability / 1200×630
HSTS Preload Eligibility
Auto-checks hstspreload.org criteria
DNSSEC Validator
AD flag / DS / DNSKEY
Cookie Inspector
Secure / HttpOnly / SameSite / __Host-
CORS Tester
Preflight + actual request
Cache Header Analyzer
Cache-Control / ETag / CDN
What Is My IP
IP / rDNS / proxy headers / UA
DNS Propagation
Cloudflare / Google / Quad9 / AdGuard
Email Auth
SPF / DKIM / DMARC / MTA-STS
TLS / Cipher Analyzer
TLS 1.0 / 1.1 / 1.2 / 1.3
Sitemap Validator
URL count / lastmod / hreflang
Redirect Chain
301 / 302 hops visualizer
Whois Lookup
Registrant · expiry · NS