Frequently Asked Questions
Is SSL Checker really free?
Yes — completely free, no signup, no credit card, and no rate limits. We run it because we use it ourselves when onboarding clients and diagnosing certificate issues. Ads on the page help cover hosting, but the tool itself will always be free to use.
How often should I check my SSL certificate?
Certificates should be monitored continuously, not just checked manually. At a minimum, run a check 30 days before the certificate's expiry date so you have time to renew. If you manage multiple domains or the cert is critical to your business, we recommend automating the check — we'll happily check your certificate as often as you need.
What's the difference between DV, OV, and EV certificates?
Domain Validated (DV) certificates only verify that you control the domain — they're free (via Let's Encrypt) and widely used. Organisation Validated (OV) certificates additionally verify that your organisation exists and is legitimate. Extended Validation (EV) certificates go further with a full legal entity check. For most websites, DV is perfectly fine. OV and EV matter mainly for banks, large ecommerce sites, and legacy browser UI treatments.
Why does the certificate chain matter?
Browsers don't trust your certificate directly — they trust it because it's signed by an intermediate certificate, which is signed by a root certificate that's in the browser's trust store. If your server is missing intermediate certificates, some clients will fail validation even though the cert itself is valid. SSL Checker verifies the full chain and flags missing intermediates, which is one of the most common configuration mistakes we see.
What happens when a certificate expires?
Modern browsers will block the page with a full-screen warning ("Your connection is not private") and make it extremely difficult for visitors to proceed. Search engines drop expired-cert sites from results within hours. Any integrations that make HTTPS requests to your server will start failing. In short: never let a certificate expire. Automate renewal wherever possible.
Can I check certificates on ports other than 443?
Yes — some services run TLS on non-standard ports (465 for SMTPS, 993 for IMAPS, 5432 for secured PostgreSQL, etc.). If your service listens on a port other than 443, include it in the URL (e.g., example.com:8443) and SSL Checker will connect to the right place.
Is my own traffic safe from SSL Checker?
Absolutely. SSL Checker only opens a TLS connection to read the certificate — it doesn't send any data to your server beyond the standard handshake, doesn't intercept traffic from your real users, and doesn't store any of the results. See our privacy policy for the full details.