Practical VPN checks: what to measure before connecting, after connecting, and when a site or mobile network fails.
Open privacy guidesCompare the public IP before and after VPN connection. For split tunneling, test protected and excluded apps separately.
Record resolvers without VPN, then with VPN. If you see an ISP or Private DNS hostname, open DNS diagnostics.
Check whether the browser exposes a local or public address through WebRTC, then repeat in another browser.
Run the same test against one server before and after VPN, then compare Wi-Fi and mobile data.
If one site fails, compare another VPN server, another network, and direct access.