It has been over a decade when IPv6 (Internet Protocol version 6) was introduced and made a part of all the mainstream operating systems. On Windows operating systems, IPv6 has been enabled for all the network interface since the Windows 8. Even after this, not many systems connect to the internet using the IPv6 networking.
There could be many reasons for the lack of IPv6 connectivity. For example, some internet service providers (ISP) have been using IPv4 only since it is still supported by all the platforms. They are taking a very long time to upgrade to the new IPv6.
Another reason for missing IPv6 connectivity is that many Windows users configured their PC to work with older IPv4 networks and have not enabled the IPv6 in the settings for their network interfaces.
No matter what the reason is, you can find out whether your system is ready and is actively using IPv6 easily through a web app called Test Your IPv6. All you have to do is visit https://www.test-ipv6.com/ in your Chrome or Vivaldi web browser.
As soon as you visit this website, it will start scanning your network connection for the presence of IPv6. According to the status displayed, it performs 10 different tests. Some of these tests include whether you have IPv6 address assigned to your system, whether you are using IPv6 DNS servers, whether you are using an ISP that is know to use IPv6 networks etc. In addition, it also performs test for the IPv4 connectivity for backward compatibility.
You can check all of these tests and their results from under the Tests Run tab. If it finds that you are using IPv6 connectivity, you are given a 10/10 score. Now you can also test many sites that are accessible only through IPv6 networks. You can find a big list of all these IPv6 only websites from under the Other IPv6 Sites.