SSL Lookup
Use SSL Lookup to inspect the certificate presented by a website. Review the returned details and understand what a certificate check can and cannot establish.
SSL Lookup for website certificate details
SSL Lookup helps you inspect the certificate presented when connecting to a website. Use the returned information as a starting point when investigating an HTTPS connection, a certificate change, or a difference between hostnames.
How to approach a certificate lookup
Enter a domain in Host, for example example.com. Use the Port field to choose the TLS service to check; the default is 443 for HTTPS. Select Submit to run the lookup. Check the exact hostname involved in your issue rather than assuming the root domain and every subdomain present the same certificate. Keep the input with your findings so you can compare like-for-like results.
Review the returned details
Inspect the certificate information that the tool actually returns. When validity dates and covered names are available, compare them with the hostname and connection you intended to test. A certificate presented by an intermediary or delivery network may differ from one configured on an origin server.
A certificate lookup is one part of connection troubleshooting. It does not establish that every page is trustworthy, that an application has no vulnerabilities, or that every visitor sees the same connection behavior.
Common questions
Does a certificate prove the website is legitimate?
It provides information used in an encrypted connection. It is not a complete assessment of the operator, content, or safety of a transaction.
Why check the exact hostname?
Different hostnames can have different configurations. Repeat a comparison using the same target when investigating a change.
Related checks
Use DNS Lookup to inspect domain records, HTTP headers lookup to review a response, and IP Lookup to inspect approximate address details.
Similar tools
Use Reverse IP Lookup to look for a host name associated with an IP address. Review the result, understand its limits, and continue your network checks.
Use DNS Lookup to check domain records, including A, AAAA, MX, NS, TXT, and SOA. Review host details and troubleshoot website or email configuration.
Use IP Lookup to review approximate location and timezone details for an IP address. Understand the results and their limits before drawing conclusions.
Use Whois Lookup to review available domain registration details. Enter a domain name, interpret public records, and investigate registrar or nameserver information.
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