SSL Certificate Checker
Verify your SSL certificate is valid, trusted, and not about to expire — an expired cert throws a full-screen browser warning that kills every visitor and tanks your rankings.
§ what this tool checks
Rules applied to every scan.
An expired or untrusted SSL certificate replaces your site with a full-screen "Your connection is not private" warning — and search engines drop sites they can't securely reach. Certificates renew silently until the day they don't. This tool connects to your domain over TLS, reads the live certificate, and tells you who issued it, when it expires, and whether the chain is trusted.
HTTPS is served and HTTP redirects to it
Certificate expiry date and days remaining
Issuer (certificate authority) and subject
Certificate chain is trusted (not self-signed)
TLS protocol version negotiated
Subject Alternative Names (covered domains)
§ faq
Questions, answered.
What happens when an SSL certificate expires?
When a certificate expires, browsers show a full-screen "Your connection is not private" (NET::ERR_CERT_DATE_INVALID) warning that most visitors will not click past. Forms stop submitting, APIs fail, and search engines that re-crawl your site over HTTPS can drop it from the index. Certificate expiry is one of the most common and most preventable causes of sudden, total outages.
How many days before expiry should I renew?
Renew at least 30 days before expiry. Most certificate authorities and tools like Let's Encrypt auto-renew at the 30-day mark, but auto-renewal can silently fail (DNS changes, rate limits, expired payment methods). Treat anything under 14 days as urgent and anything already expired as a live outage.
What does "certificate not trusted" mean?
A certificate is trusted when it chains up to a certificate authority that browsers ship in their root store. "Not trusted" usually means the certificate is self-signed, the intermediate certificate is missing from your server configuration, or it was issued by an authority browsers do not recognize. Even a valid, unexpired self-signed certificate triggers a browser warning.
Does HTTPS actually affect SEO?
Yes. Google has used HTTPS as a lightweight ranking signal since 2014, and Chrome marks plain HTTP pages as "Not Secure." More importantly, a broken or expired certificate makes your pages unreachable to crawlers over HTTPS, which causes ranking and indexing losses far larger than the modest HTTPS boost itself.
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