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VPN testing checklist

 To test:

  • Is VPN active?

  • Is it leaking?

  • Does it look residential?

  • Does it alter network fingerprints?



  1. Public IP Test (Basic Detection) - curl ipinfo.io
  2. DNS Leak Test - nslookup google.com
  3. MTU Test (Encapsulation Detection) - ping 8.8.8.8 -f -l 1472
  4. TCP MSS Inspection - Use Wireshark and Look for SYN packets.
  5. Traceroute Path Test - tracert 8.8.8.8
  6. WebRTC Leak Test - browserleaks.com/webrtc
  7. IPv6 Leak Test - test-ipv6.com
  8. Latency / Jitter Test - ping -n 50 8.8.8.8. VPN usually causes: More Jitters and Latency.
  9. Reverse DNS (PTR Record) - nslookup <your-public-ip>
  10. IP Reputation Check - Like most IP's from VPN Providers like Express VPN, etc. are blacklisted and all. Look for: Proxy/VPN classification, Hosting provider tagging

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