Security Tools

Free Security Tools

Free, passive tools for checking domains, email security, passwords, files and links. Nothing here scans, probes or attacks any system. Built-in tools run in your browser, and lookups read only public DNS and registration data.

Open the tools

What's included

Domain, DNS and registration

DNS lookups over HTTPS, an email security check (MX, SPF, DMARC, MTA-STS, TLS reporting, BIMI, CAA, DNSSEC and DKIM) and registration (RDAP) lookups for domains, IP addresses and networks.

Passwords and passphrases

A password strength meter, a breach check that never sends your password (it uses k-anonymity), and a passphrase generator. All three run in your browser.

Analysis helpers

Hash calculator, encoders and decoders, JWT decoder, email header analyzer, URL inspector, subnet calculator and CVSS 3.1 calculator.

Links to well-known free services

Shortcuts to established free services for checking files, links and website certificates. They open in a new tab and are run by their own providers, not by CSMIC.

Fair use and availability

Access needs a quick check and is available to visitors from Canada, the United States, the United Kingdom, Western Europe, Australia, New Zealand and selected partner countries. Use the tools only for lawful, defensive purposes.