Free SSL Certificate Checker

The padlock in your browser bar hides a surprising amount of confusion, so let's clear it up. So what is HTTPS? At its core it's just HTTP with an encrypted layer underneath — the "S" literally stands for "Secure." That layer is what stops anyone between your visitor and your server from reading or tampering with the traffic, which is why browsers now slap a "Not Secure" warning on any site still running plain HTTP.

And what does SSL mean? SSL — Secure Sockets Layer — is the technology that does the encrypting, or at least it was the name for it. So is HTTPS secure? The honest answer is: yes, as long as the certificate behind it is valid, current, and trusted. A padlock only means the connection is encrypted; it says nothing about whether the site itself is trustworthy, which is a distinction phishing sites happily exploit.

Here's the twist almost nobody mentions: "SSL" has been dead for years. The protocol was renamed TLS (Transport Layer Security) back in 1999, and every version actually called SSL has since been broken and retired. When you buy an "SSL certificate" today, you're buying a TLS certificate — the old name just stuck because it's what everyone searches for.

The version your server negotiates is a real security signal, not trivia. Weigh TLS 1.2 vs 1.3 and you'll find they're the only two versions considered safe today; anything older (TLS 1.0, 1.1, or genuine SSL) is deprecated and flags you in security scans and compliance audits like PCI DSS. TLS 1.3 is the one to aim for — it's faster and drops the weak options entirely. The checker above reports which version your site negotiates, so you can spot a server that's quietly stuck on an outdated one.

"SSL certificate" isn't one thing — it's a category, and picking the wrong one is a common, expensive mistake. Certificates differ on two axes: how much the authority verified you, and how many names the certificate covers.

On verification, there are three levels:

A certificate is only worth something because a Certificate Authority (CA) — an organisation browsers have agreed to trust, like Let's Encrypt (which hands out a free TLS certificate to anyone), DigiCert, or Sectigo — vouches for it. Your certificate is signed by the CA, the CA's certificate is signed by a root, and that root ships pre-trusted inside every browser and operating system. That linked path is the "chain of trust," and every link has to check out for the padlock to appear.

This is why a certificate can be perfectly valid and still throw a "not secure" warning. A self-signed certificate — one you issued yourself, with no CA behind it — has no chain to a trusted root, so browsers reject it (fine for a local test server, never for production). More often the certificate is genuine but the server was set up without its intermediate certificate, breaking the chain halfway. The checker walks the chain and reports the trust status, so you catch a broken link before your visitors hit the warning screen.

Running a domain through the tool above tells you exactly where you stand right now: the expiry date, days remaining, the issuer, the TLS version, and whether the chain is trusted — in a couple of seconds, no sign-up. Perfect for a quick audit or confirming a certificate you just installed.

But an SSL certificate isn't a set-and-forget thing. Let's Encrypt certificates last just 90 days, auto-renewal fails more often than anyone admits, and expiries have a cruel habit of landing on a weekend when nobody's watching — taking the whole site down with a full-page browser warning. That's the gap Uptura closes: add your domains and it checks every certificate on a schedule, then alerts you by email and Slack as each one nears expiry, so a forgotten renewal never becomes an outage.