Free Online Security Tools

No sign-up. No installation. Instant results.

Online Subdomain Finder

Discover subdomains without installing anything. Free, no sign-up required.

Header Security Checker

Instantly analyse the HTTP security headers of any public URL.

DNS Lookup Tool

Free online DNS lookup. Check A, AAAA, MX, TXT and NS records instantly.

Runs on our servers. Nothing to install, nothing to configure.

Subdomains are read from public Certificate Transparency archives, never by probing the domain.

Ten requests a minute. No account, no API key.

Need more than three tools?

The full platform runs 88 security tools across 14 categories against targets you own — scheduled, with reports that say how to fix what they find.