SSL Certificate Checker
Check any HTTPS site's certificate expiry, issuer, and chain validity in seconds — and see which TLS versions the server still allows.
Why SSL certificates expire without warning
Every SSL/TLS certificate has a fixed validity window — often 90 days for free certificates like Let's Encrypt. When it lapses, browsers show a full-page security warning and most visitors leave immediately.
Renewals are supposed to be automatic, but they quietly fail all the time: a cron job stops running, a DNS challenge breaks, or a load balancer keeps serving the old certificate. Nothing tells you until traffic drops.
What this checker verifies
This tool opens a real TLS connection to your domain and reads the certificate the server presents. It shows the expiry date and days remaining, who issued it, whether the chain is complete and trusted, whether the hostname matches, and which TLS version was negotiated.
It never stores your site or requires a login — it's a read-only inspection you can run as often as you need.
How do I check when an SSL certificate expires?
Enter your domain above and run the check. The tool connects over HTTPS, reads the certificate, and shows the exact expiry date along with how many days are left.
What does an invalid or incomplete certificate chain mean?
A certificate is trusted only if every certificate between it and a trusted root is present. If the server omits an intermediate certificate the chain is 'incomplete' — some browsers still work while others show errors, which makes it hard to diagnose. This tool flags that case explicitly.
Which TLS versions are still safe to use?
TLS 1.2 and TLS 1.3 are considered secure. TLS 1.0 and 1.1 are deprecated and should be disabled. If the server still allows them, this checker flags it as legacy TLS.
Can Narvin alert me before my certificate expires?
Yes. Narvin monitors your certificate continuously and alerts you (email, Slack, and more) 30 days before expiry, so a silent renewal failure never becomes downtime.
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