If you can't get a connection, click 'Check connection'. Eventually, your browser asks you to accept smartChords self-signed certificate.
Newer browsers do not trust self-signed certificate. This is because they do not know who issued the certificate.
To be on the safe side, they block them by default.
Steps for Firefox:
1. Click on 'Check connection'
2. Press the 'Advanced' button
3. Accept the risk and continue. After that, you can test the online tool again
Steps for Chrome:
1. Click on 'Check connection'
2. Press the 'Advanced' button.
3. Click 'Proceed to xxx.xxx.xxx.xxx (unsave)'. After that, you can test the online tool again