available as 'ready-to-go' Docker package

November 13, 2023
Today launches a new version of its test tool in the form of a 'ready-to-go' package based on Docker. It makes deploying, developing, testing and scaling the code base much easier. In addition, in this new version, the Referrer-Policy test has been extended to evaluate found policies and several other improvements have been made. Happy testing!

'Ready-to-go' Docker package

Up until now, setting up was challenging and cumbersome. Many times this annoyed ourselves, and also hindered others who wanted to use and contribute to the codebase. Over the last months, the code has been carefully assembled into a 'ready-to-go' software package, i.e. a Docker container.

"We believe this 'containerisation' of is a huge step forward", says Gerben Klein Baltink, chairman of Platform Internet Standards, which is developing "The 'ready-to-go' package makes using the code more user-friendly for ourselves and for others. This also contributes to the quality of the code."

This new version will make it much easier for others to use the code on their own servers, as (Australia), (Brazil) and sikkerpå (Denmark) already do. Furthermore, it will make it easier for external developers to contribute code to the project.

More tests

We expect this all will result in more websites, mail servers and connections being tested for modern Internet standards. Not only on our own servers which have run over 5 million tests in the last 12 months, but also on the servers of others. This way we hope to further accelerate the worldwide use of modern Internet standards making the Internet more accessible, safer and more reliable for everyone.

You are very much invited to deploy and use this new version on your own system, as single test version (website) or as batch test version (API). However, please note that if you run the code on a public web server, you may not use the name or logo.


This project would not have been possible without the support from SIDN Fund. Therefore, we would like to thank them very much!

Extended Referrer-Policy test

The Referrer-Policy test now also checks for a sufficiently secure and privacy-protecting policy value. With this policy your webserver instructs browsers if, what and when referrer data should be sent to the website the user is navigating to from your website.

The data in the Referer header is usually used for analytics and logging. However there can be privacy and security risks. The data could be used e.g. for user tracking and the data could leak to third parties who eavesdrop the connection. To mitigate these risks it is important to set a Referrer-Policy with a sufficiently secure and privacy-protecting policy.


The test tool is an initiative of the Dutch Internet Standards Platform which is a collaboration of partners from the Internet community and the Dutch government. The aim of the platform is to jointly increase the use of modern Internet standards to make the Internet more accessible, safer and more reliable for everyone. The software code of is available under an open source license.

Release notes 1.8.0

This release has API version 2.4.0:

  • The referrer_policy_errors and referrer_policy_recommendations fields were added. These contain errors and/or recommendations regarding the Referrer-Policy test.