Web Toolarium

SSL / HTTPS CHECK

SSL Check

Check a domain’s SSL certificate, HTTPS connection, and TLS status. Results describe facts observed during the check.

CHECK A DOMAIN

Check SSL / HTTPS status

Our server connects to the host you enter to inspect its certificate and HTTPS response.

Port 443 is used. Localhost, private IPs, URLs with credentials, and custom ports cannot be checked.

Scope and privacy

Your input is used temporarily for this check. We do not save domain history or fetch page content. These results do not guarantee the overall safety of a site.

ABOUT THIS TOOL

Understanding SSL certificates and HTTPS

What is an SSL certificate?

A digital certificate used to identify a server and encrypt communication. Check its validity, hostname, issuer, and SAN.

CN and SAN

SAN is the primary source for hostname matching today. One certificate can list multiple hostnames.

What is TLS?

TLS protects HTTPS connections. This page shows the version and cipher suite negotiated for the actual connection.

What this check covers

This checks the certificate, HTTPS response, TLS details, and certificate-chain overview. It does not assess the whole site’s security.

HOW TO USE

How to use the checker

Enter a domain to check its certificate and HTTPS connection together.

01

Enter a domain

Enter a domain or URL, such as example.com or https://example.com/.

02

Check SSL

Select the button to check the host from our server.

03

Review the results

Review expiration, hostname, issuer, HTTPS response, TLS details, and the certificate chain.

Results reflect the connection to the host at the time of the check. They do not assess the whole site or its page content.

WHEN TO USE IT

When this tool can help

Before renewal

Check the expiration date and remaining days to plan a renewal.

After launch or migration

Confirm the expected certificate after changing a server or DNS.

Investigating HTTPS errors

Narrow down the cause of a certificate warning or connection error.

Reviewing certificate details

Inspect the subject, issuer, SAN, and fingerprints.

Reviewing TLS settings

Inspect the TLS version and cipher suite used by the connection.

Checking from another network

See the certificate and HTTPS response from a server outside your own device.

QUESTIONS & ANSWERS

SSL checker Q&A

Answers to common questions about the results and checks.

Q1 What is an SSL certificate?

A digital certificate used to identify a server and encrypt communication. Check its validity, hostname, issuer, and SAN.

Q2 Are SSL and TLS the same?

TLS protects HTTPS connections. This page shows the version and cipher suite negotiated for the actual connection.

Q3 What does a hostname mismatch mean?

SAN is the primary source for hostname matching today. One certificate can list multiple hostnames.

Q4 Should I enter a URL or a domain?

Enter a domain or URL, such as example.com or https://example.com/.

Q5 Why can HTTPS fail when the certificate is valid?

TLS, the HTTP response, and source-network restrictions can fail independently. A valid certificate alone does not guarantee an HTTPS response.

Q6 What is a self-signed certificate?

A certificate signed by itself or its operator rather than a trusted certificate authority. It may be intentional in internal environments.

Q7 What is SAN used for?

SAN is the primary source for hostname matching today. One certificate can list multiple hostnames.

Q8 How are the remaining days calculated?

It is an estimate based on the difference between the expiration time and the check time. Renew well before expiration.

Q9 What does successful chain validation mean?

It means the certificate path to the host could be trusted. The root certificate may not be shown.

Q10 Are my domain or page contents stored?

Your input is used temporarily for this check. We do not save domain history or fetch page content. These results do not guarantee the overall safety of a site.