Network Diagnosis
Diagnose your connection, DNS, IPv6 and the node you are connected through — in your browser.
Nothing, including your IP address, is sent to or stored on a server. Diagnosis runs entirely in your browser.
Diagnosing…
Connection change watch
Connection changes (online/offline/network switches) will be recorded here.
For deeper checks
- DNS Leak Test: detailed DNS leak check
- Packet Loss Test: packet loss check
What is this tool?
A free network diagnosis that runs when the page opens. It checks whether your device is online, whether DNS works, and whether you can reach the outside network, then shows your connection details and keeps watch for changes.
How to use
- Open the page — the diagnosis runs automatically.
- Follow the 3-step breakdown to find where a problem is.
- Use the change watch to compare before/after switching networks or VPN.
Use cases
- Narrowing down why a site does not load.
- Checking whether IPv6 is available on your connection.
- Confirming a VPN actually changed your IP and route.
Notes
- Browser-based checks may differ from system-level tools.
- Results stay in your browser; nothing is sent or stored remotely.
FAQ
Is my IP address sent anywhere?
No. Results, including your IP address, are shown only in your browser and never stored or sent to a server. IPs are masked by default — reveal them only when you need to.
What does the 3-step check do?
It checks whether your device is online, whether DNS name resolution works, and whether you can reach the outside network — narrowing down where a connection problem lives.
What is the connection change watch?
It re-runs the diagnosis when your connection changes (Wi-Fi switches, VPN on/off) and logs what changed, such as your IP address or connected CDN node.
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