GOV.UK Pulse measures the strength of HTTPS in place on any given domain.
Currently, GOV.UK Pulse uses the official .gov.uk domain list as a starting point. Unfortunately this list is only updated once every year.
HTTPS provides a secure connection across the internet between websites and their visitors, and is becoming the new baseline for public web services across the internet.
Note that HTTPS generally does not affect whether a website is vulnerable to hacking.
The list of GOV.UK domains used was generated on October 1, 2015.
HTTPS and TLS data is automatically collected daily.
If you just changed something about your domain to address an issue on GOV.UK Pulse, be aware that data does not update instantaneously, and so there may be a delay before your domain's information updates.
Please note that this website is currently an experiment and still in beta testing. If you see a mistake, please contact me on Twitter.
You can find the code behind the the scanner and website on Github.
SSL Labs is a free online service that analyses the configuration of web servers on the public Internet.