Together with Afnic, The Swedish Internet Foundation has developed the DNS testing tool Zonemaster. The goal is that the partnership will result in Zonemaster becoming the de facto standard for DNS tests.

Zonemaster is a program designed to help people to control, measure and hopefully better understand how the DNS, domain name system, works.

How it works

Zonemaster consists of three main parts: The engine (the code that performs all tests), command line interface (CLI) and web interface. When a domain name (also called zone) is sent to Zonemaster, the program then examines the domain name’s state of health through traversing the DNS from the root (.) to the TLD (top level domain, for example .NET) and finally the DNS servers that contain information about the specific domain name (for example, Zonemaster also performs many other tests which are documented here: Test Requirements document.


Zonemaster is accessible to everyone and it is possible for anyone to check your domain name and also see the test history for your domain name. However, there is no way to see who has run a test since the only thing logged is the date when the test was performed.

International cooperation

Zonemaster is the result of a cooperation between The Swedish Internet Foundation (Registry for the TLDs .se and .nu) and AFNIC (Registry for the TLD .fr and the smaller TLDs belonging to France).