This page describes how to observe Chrome's CT state for a secure site.
This feature is available since Chrome 33 (the strings will have changed in Chrome 44).
This information is present in the Connection information pop-up in Chrome. Click the padlock:
Then navigate to the Connection Information tab:
The Certificate Transparency status is now a part of the website identity string. For example, when a valid Signed Certificate Timestamp accompanies the certificate, the string would read like so:
One of four strings will be displayed:
The exact Signed Certificate Timestamps Chrome sees and their validation status is available through Chrome's NetLog, accessible via
The chrome NetLog should be opened before visiting a website. Then switch to the Events view from the drop-down and look for a 'SOCKET' event type.
Past the certificate chain, the SCTs received, their origin and validation status will show:
Specifying a custom CT log
By default, Chrome will check SCTs coming from a list of predefined CT logs recognized by Chrome. The next step is only necessary if you wish to get Chrome to check an SCT issued by your own log. If so, launch the binary with the following command:
The flag format is described in this page.
Note: The SCT Viewer has been removed from Chromium since it was missing from the Mac version of Chrome and there were no immediate plans to amend it (announcement).
The information below is for historical reasons only.
In addition to the basic UI indicator, it is possible to view details about each Signed Certificate Timestamp.
When Signed Certificate Timestamps are present, the "Transparency information" link (which can be seen on the screenshot above) will pop up a dialog showing details about the Signed Certificate Timestamps:
This viewer is available in Chrome for Windows or Linux since release 35.