Glossary · Proxy types
Open proxy
A proxy that accepts connections from anyone with no authentication, which is what almost every address on a free proxy list actually is.
An open proxy answers whoever connects to it, with no username, no key and no allow-list. Some are deliberately public, but a great many are servers left misconfigured, which is why open proxies appear and vanish constantly and why no two lists of them agree for long.
Being open is also what makes them findable. Anyone can scan for a listening proxy, confirm it forwards traffic, and republish it, so the same address propagates across dozens of lists at once. That reach is the appeal for casual use and the risk for anything sensitive: an open proxy is shared with strangers by definition, and traffic sent through one unencrypted can be read by whoever runs it.
The honest way to describe a pool of them is by behaviour over time, not a headline count. An address that answered an hour ago may be gone now, so the useful question is not how many were ever listed but how many respond to a live check right now.
How HProxy handles it
Our free list is built entirely from open proxies, and we keep a permanent record of every one we have ever seen, live or long dead. The majority never answered a single check across their whole history, which is exactly why we re-verify continuously rather than trusting a source's claim that an address works.
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