Your domain
The requested hostname must be covered by the certificate.
Tools for your website
Trust starts with HTTPS
Inspect the certificate your website presents to visitors: which domain it covers, when it expires and whether its trust chain validates.
Start a checkOnline check
SSL check
Check result
Your archive
Check history
Without signing in, history is kept for 30 days in this browser. In your account, it is kept for 365 days.
Your checks across all tools will appear here.
How trust works
A certificate is part of a chain
Validity, website identity and issuer trust are separate checks. One passing result does not replace the others.
Website certificate
Validity period, signature and intermediate certificates.
Trusted authority
The chain must lead to a trusted root authority.
This explains the principle. Run a check to see the actual result for your domain.
Clear diagnostics
The browser padlock depends on the details
Even an unexpired certificate can trigger a warning if it does not match the website name or the server sends an incomplete chain. The check helps distinguish these issues and identify what needs attention.
- 01
Enter the website name
Enter the domain your visitors open. You can check the www and non-www versions separately.
- 02
Inspect the certificate
The tool checks the HTTPS connection on the standard port 443 and the certificate presented by the server.
- 03
Review warnings
Compare the domain name, dates and trust validation result. Run another check after updating the configuration.
General iT is here to help
A check is the first step. We help with the fix.
For help configuring your website or keeping it reliable, choose a service that fits the task.
01
SSL certificates
Choose a certificate for your project’s domains and requirements.
Explore the service02Server administration
Configure HTTPS and the certificate chain on your server.
Explore the service03Managed maintenance
Put website and infrastructure maintenance in the hands of one team.
Explore the serviceQuestions and answers
What to know
What does the SSL tool check?
The tool checks the connection on port 443, the presented certificate, its validity period, hostname match and trust chain. It diagnoses certificate configuration; it is not a complete server vulnerability audit.
Are SSL and TLS the same thing?
TLS is the protocol used for modern secure connections. The term “SSL certificate” is still widely used for HTTPS certificates, even though the connection normally uses TLS.
Why is there a browser error if the certificate has not expired?
Possible causes include a hostname mismatch, an incomplete certificate chain or an untrusted issuer. Also check the date on the device. Identify the cause from the specific warning, rather than relying only on the expiry date.
Does the check inspect every server behind a domain?
No. The result applies to the connection made during that check. If a domain uses multiple nodes or distributed delivery, certificates on other nodes may differ.
Can I compare certificates before and after replacement?
Yes. Open the saved checks in your history. Guests can access them in the same browser for up to 30 days; signed-in users keep them in their account for up to 365 days.
Check when an SSL certificate expires
The expiry date helps you prepare a certificate replacement in time. Check the certificate the server actually presents to visitors: uploading a new file does not mean it is in use. After replacement, another check shows the certificate used in a new connection.
Trust chain and domain name
Correct HTTPS depends on more than dates. The certificate must cover the name the visitor entered, and the server must provide a suitable chain. Checking these conditions helps diagnose warnings after a website migration, certificate replacement or web server configuration change.