Culvert VPNHow to check your VPN is working
Compare the IP address a website sees before and after you connect; if it changes to the server's address and DNS follows, the VPN is working.
Testing and troubleshooting
Connected is not the same as protected. These guides show how to check a VPN is really working, how to test for IP, DNS and WebRTC leaks on Android, what common error messages mean, and what to try when a VPN will not connect or drops when the screen turns off.
10 guides · RSS
How to test for an IP leak
An IP leak means a site sees your real address while the VPN is on. Compare IPv4 and IPv6 with the VPN off and on, then again after a reconnect.
How to run a DNS leak test on Android
A DNS leak test shows which resolver answered your lookups while the VPN was on; if it belongs to your carrier or ISP instead of the VPN, DNS is leaking.
WebRTC leaks: what they are, and whether Android apps are affected
A WebRTC leak is a browser handing your real IP to a web page while a VPN is on; mainly a desktop problem, and Android apps with no browser are unaffected.
VPN not connecting on Android: a checklist
A VPN that will not connect on Android usually has no internet underneath, a filtering network, a revoked permission or a wrong clock; check in that order.
"Authentication failed" and other VPN errors, decoded
On a VPN app with no password, "authentication failed" almost always means an expired session or a wrong phone clock. Fix the time and reconnect first.
Why a VPN should verify its own exit IP
A VPN app should confirm the tunnel works by asking its own server what address it saw, through the tunnel, not by loading a third-party IP-lookup page.
VPN disconnects when the screen turns off
A VPN that drops when the screen turns off is usually stopped by Android's battery optimisation or a manufacturer task killer; exempt it and use Always-on.
Fast at home, slow at work: read the network, not the app
When the same VPN is fast on one network and slow on another, the slow network is almost always filtering UDP, forcing the app onto a slower TCP method.
Reading a VPN connect screen: down, up, session, exit IP
Down and up are tunnel throughput, session is time since the tunnel came up, and the exit IP is the address sites see; here is what each one tells you.