Free SSL & DNS Checker
Enter any domain to see its TLS certificate expiry, issuer, and live DNS records — instantly, with no signup. Then let Merlonix watch it for you around the clock.
What does the free SSL & DNS checker check?
The checker reads the same public signals Merlonix monitors continuously: your TLS certificate's issuer, validity window, days until expiry, and the hostnames it covers; the domain's A/AAAA, MX, and NS records; and the domain's registration expiry. Everything here is public information — no account or verification needed.
Why does SSL and DNS health matter?
An expired certificate takes a site offline for every visitor and erodes trust instantly. DNS drift can silently reroute traffic or break email, and a lapsed domain registration takes everything down at once. A one-time check tells you where things stand today; continuous monitoring is what catches the expiry that's 21 days out — before it becomes an incident.
How do I monitor a domain continuously?
Merlonix watches SSL expiry, DNS configuration, domain registration, and uptime across every domain you (or your clients) depend on, and alerts you the moment something changes. Run a check above, then claim the free plan ($0, no credit card) to keep one domain monitored, or start a 14-day trial for the full workspace.