With the SSL certificate check tool, you can do a full check of the entire certificate chain of
trust - from the end user website certificate and to the root certificate.
You can see all available details about each certificate.
The tool also validates each certificate according to all common standards.
For a quick introduction, you may try out a couple of samples:
If you would like to see checks that fail,
badssl.com provides
some excelent samples:
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