SSL Certificate Checker
SSL Certificate Checker — paste a URL and get the answer in seconds.
This performs a real TLS handshake with the host and reports who issued the certificate, who it was issued to, when it expires, how many days remain, which TLS version and cipher were negotiated, and every hostname it covers. An expired certificate shows every visitor a full-page security warning, so knowing the date in advance matters.
Frequently Asked Questions
How do I use the ssl certificate checker?
Paste the URL into the box and press the button. The check runs on our server — not in your browser — because browsers are not allowed to read another site’s response, and the result appears within a few seconds.
How many days before expiry should I renew?
Renew at 30 days remaining and investigate immediately below 15. Let’s Encrypt certificates last 90 days and are meant to auto-renew at 30 — if yours is under that, the renewal has probably failed silently and will not fix itself.
Why does this one need a server when your other tools do not?
The browser’s same-origin policy stops JavaScript reading a response from another website, and a browser has no access at all to a TLS certificate chain. Almost every tool on this site runs entirely on your device; these few genuinely cannot, so they run on ours instead.
Do you store the URLs I check?
No. The request is made, the answer is returned to you, and nothing about it is kept.
Can I check a site that is not mine?
Yes — everything here reads only what the site already serves publicly to any visitor. Nothing is scanned, probed or attacked; it is the same information your own browser fetches when it loads the page.