|Developer(s)||Fabian Keil and David Schmidt|
3.0.28 / 1 Jan 2019
|Operating system||Linux, Windows, Mac OS X, AmigaOS and BeOS|
Privoxy is a advanced web filtering proxy which can be used to remove advertisements, banners and pop-ups, manage cookies, modify webpages, rewrite http headers and more. It basically removes Internet junk and protects your privacy. It is amazingly configurable and you can create very advanced filtering rules based on your own preferences.
Why you want(ed) Privoxy
Privoxy used to be a really good way to remove ALL the advertisements and junk you encounter on the Internet. This is, sadly, no longer the case as more and more websites have moved to https. privoxy and filtering proxies can only work on http so they are ineffective if a site uses the encrypted https protocol.
Many websites on the web today contain two things: Content and Junk.
(Advertisements, blank images who are only used for tracking, etc). Privoxy can remove all the junk and give you webpages who only contain actual content.
Example: The image to the right as advertisements (mind-controlled propaganda designed to artificially create wants for products you do not want or need), the one to the left is loaded through privoxy:
Caching Proxy Frontend
If you or your corporation are using a cacheing web proxy such as Squid or Polipo then you may want to consider putting Privoxy in front of them (Browser -> Squid -> Privoxy) to remove junk and save bandwidth.
Privoxy can filter the http headers and the elements on websites who are commonly used to track what you and your loved ones are doing on the Internet. This will slightly increase your privacy.
If you really want privacy then you should use Tor (it's easy to setup, read how) in combination with Privoxy. Tor will hide your IP and give you [[traffic analysis]] resistance, Privoxy will filter away clues which can be used to track you over the anonymous Tor-connection.
Why you may want to think twice about using Privoxy
It must be mentioned that Privoxy will use quite a lot of CPU. This makes absolutely no difference when you're running it locally on a Athlon2k or something like that, but it will seriously slow you down if you're using Lynx on a Pentium II.
- Web browser (Konqueror/Seamonkey/Firefox) -> Privoxy -> Squid -> Website
A setup only using Privoxy (Browser -> Privoxy -> Website) will save you bandwidth even though it does not cache because Privoxy doesn't load advertisements and other junk you, as a user, likely don't want anyway.
Tor is a popular anonymity network which hides your IP from the websites you visit. Users of Tor should use Privoxy or Polipo to filter away information which is typically leaked by web browsers. Tor is slower than normal web browsing, so many Tor-users wisely combine Privoxy with a cache.
Such setups typically go:
Web browser -> Privoxy -> Squid -> Tor -> Website
Privoxy makes your browser (application) behave anonymously. Tor makes your connection (TCP-stream) anonymous.
Tor + Privoxy == Excellent and low recommended combination.
Whole books can and probably will be written about Privoxy's various configuration options.
The default out-of-the-box should work well for most people (n00bs), but advanced users (l33t) can spend hours reading about all the configuration options and still not be aware of all of it's features. In short, if you need some kind of strange proxy-filter functionality then you'll much likely find that there is a Privoxy filter rule option just for you which does exactly what you are looking for.
The filter rules can be limited to the whole web, a top level domain, a domain, a subdomain or a URL.
Privoxy is by default configured to behave according to three rulesets: standard, default and user (For your own user customizations).
It must be mentioned that Privoxy's filters work with whole web pages. This means that your browser is not given anything before Privoxy had recieved and crunched the whole page. This may in some cases make big pages seem to load slower. Browsers start rendering pages as soon as they have enough of it to do so, which makes page loading seem faster, but when you are using Provoxy the browsers won't/can't do that.
It should also be mentioned that Provoxy heaves like this even if you are not using any of the content filtering; thus: If you only want Privoxy for filtering the headers and advertisements then Polipo, not Privoxy, is much likely the proxy you want.
Privoxy is based on a now unmaintained proxy called "Internet Junkbuster".
Privoxy runs just fine off Linux, Windows, Mac OS X, AmigaOS, BeOS, and most flavours of Unix.
Any web browser which supports using a http proxy (basically all of them) can use Privoxy.