Most proxy checkers miss IP leaks — here is how to properly verify anonymity

A successful proxy connection does not guarantee that your real IP address is hidden from destination servers, as many proxies silently forward it via headers like X-Forwarded-For. Proxies can be graded into three categories — transparent, anonymous, and elite — based on whether they expose the real IP or reveal that a proxy is in use at all. A developer has released an open-source command-line tool called proxyprobe that checks proxy anonymity, response times, and geolocation for bulk proxy lists with concurrency support. The tool highlights two common implementation pitfalls: greedy password masking to prevent credential leaks in logs, and configurable echo endpoints to avoid routing proxy data through unintended third parties. It is designed to integrate into CI pipelines, returning exit codes based on whether any proxies remain functional.