Tools
32 free checks. One page each, no signup. Save a domain and any of them runs daily.
DNS and domain
SSL Checker
Expiry, chain, TLS version and cipher
DMARC Checker
Policy, alignment, reporting addresses
SPF Checker
Syntax, the 10-lookup limit, +all
DKIM Checker
Selector lookup or auto-probe, key size
MX Lookup
Mail servers, priorities, provider
TXT Lookup
Every TXT record, SPF and verification tokens labelled
CNAME Lookup
Alias chain to the final address
A Record Lookup
IPv4 and IPv6 addresses with TTL
SRV Lookup
Priority, weight, port and target
DNS Propagation
12 resolvers queried in parallel
WHOIS Lookup
Registrar, dates, name servers
DNSSEC Checker
DNSKEY and DS records, signing status
Diagnostics
Security Headers
HSTS, CSP, X-Frame-Options, graded
Redirect Checker
Every redirect hop with timing
HTTP/2 and HTTP/3
ALPN and Alt-Svc
Reverse DNS
PTR record for an IP or a host
Cookie Scanner
Cookies and trackers set before consent
Cookie Audit
Secure, HttpOnly, SameSite
Domain Age
WHOIS plus the earliest CT-log entry
Security and OSINT
Subdomain Finder
Enumerated from Certificate Transparency
Blacklist Checker
8 major RBLs in parallel
Takeover Checker
Dangling CNAMEs on 16 SaaS providers
Typosquat Watcher
120+ cousin domains probed for DNS and MX
Email authentication
Email Auth Scanner
SPF, DKIM, DMARC, MX, PTR, MTA-STS in one run
Deliverability Report
Inbox probability per provider, ranked fixes
DMARC Report Analyzer
Upload a rua XML report, get sources and a verdict
DNS Record Explainer
Paste any record, get it explained tag by tag