SSL checker for your website certificate
An SSL checker connects to your web server the way a browser does and shows whether the SSL certificate is valid, when it expires, who issued it and whether the certificate chain and TLS settings are installed correctly. Our free tool is in early access.
Check your website SSL certificate
The tool is in early access. Leave your website and email and we will let you know when it opens.
What an SSL certificate checker verifies
A full check of a website SSL certificate gives more information than the padlock in the browser:
- Validity: the certificate is trusted, not self-signed and issued for this domain name.
- Expiry date: how many days are left before the certificate expires and the site shows a security warning.
- Domain coverage: which names the certificate covers, including www and subdomains.
- Certificate chain: whether the server sends the intermediate certificates, so every browser and device can verify it.
- TLS protocol: which TLS versions the server supports and whether outdated protocols are still enabled.
- HTTPS redirect: whether the HTTP version of the site redirects to HTTPS.
How to read SSL checker results
Valid and installed correctly means visitors see a secure connection and you only need to watch how many days are left until the expiry date.
Expired or expiring soon is the most common problem. Browsers block the page with a full-screen warning, and most visitors leave. Renew the certificate with your hosting provider or certificate authority; free certificates from Let's Encrypt renew automatically if auto-renewal is set up on the server.
Name mismatch means the certificate was issued for another domain or does not include www or a subdomain. Reissue it with all the names your site uses.
Incomplete chain often works in one browser and fails in another or on mobile. Install the intermediate certificates provided by your certificate authority on the web server, next to the certificate and its private key.
Old TLS versions enabled is a configuration problem on the server. Disable outdated protocols to close known vulnerabilities.
Why SSL matters for security and SEO
SSL (more precisely TLS today) encrypts the connection between the browser and the server, so passwords, forms and payments cannot be read on the way. Google uses HTTPS as a ranking signal, and browsers mark sites without a valid certificate as not secure. An expired certificate also breaks crawling: search engines and AI crawlers may stop fetching your pages until it is fixed.
Do not check by hand: monitor expiry
A one-time SSL test tells you the status today. Certificates expire on a schedule, so the safer option is monitoring.
Expiry alerts
Rankmetr monitoring warns you in Telegram before the SSL certificate or the domain expires.
Uptime in the same place
The same monitor tells you when the website stops responding. See the website down checker.
Part of the site audit
HTTPS problems also show up in the SEO checker together with redirects and broken links.
FAQ
How do I check my SSL certificate?
Click the padlock in the browser address bar to see the issuer and expiry date. For the chain, covered names and TLS versions, use a tool that tests the server directly.
How can I tell if an SSL certificate is valid?
It is valid if it is issued by a trusted certificate authority, covers the exact domain name, has not expired and the server sends the full chain. An SSL test shows all four at once.
What does SSL stand for?
Secure Sockets Layer. The protocol was replaced by TLS (Transport Layer Security) years ago, but the name SSL certificate stayed.
How often do SSL certificates expire?
Publicly trusted certificates are issued for a limited period, and the maximum period keeps getting shorter. Free Let's Encrypt certificates are short-lived and are meant to renew automatically.
Is there a difference in security between free and paid certificates?
Encryption is the same. Paid certificates differ in validation level, warranty and support, not in how well the connection is protected.
Will a check look like an attack on my site?
No. An SSL check opens one normal HTTPS connection, the same as a visitor's browser.
Get early access to the SSL checker
Leave your email and website. We will tell you when the free tool opens and can set up certificate monitoring for your site in the beta.