Does it really work? And why?

If your email address is already in the hands of spammers, this tool will not help much (though the report mentioned above states that the amount of spam will indeed decrease). You obviously need a spam filter (like spamassassin, e.g.). But if you are publishing the email address on your webpages for the first time, you will want to stop the spammers from getting your new address. Of course, one could always copy + paste the email address from the browser window. But spammers need millions of addresses. So they use robots (i.e. specialised search enginge software) that will search the web for email addresses. Usually the easiest way will be to look for "@" in the webpages, maybe for <a href="mailto:". With your email encoded neither is in the sourcecode of the webpage.

Of course it is possible that a spammer's email search robot decodes the number codes for the characters. But seemingly this is not yet common among these robots. So, for the time being, it will help a lot.

To make it harder, I am using a random mixture of decimal and hexadecimal notation of the codes so that only a robot that decodes both types can solve the puzzle and find the email addresses.

[2003-09-28] The Workgroup of Theoretical Biology at the University of Bonn is using obfuscated email addresses for approx. 9 months now. The level of incoming spam has remained quite low, even for my own address that used to be online unscrambled for quite a while before. Of course there are always some spams where the email addresses used have been generated randomly or using name lists. -- I would appreciate to hear of your experiences with obfuscated email addresses.

Also recent legislative, like the DMCA in the US or "Paragraf 52a" of the new version of the German "Urheberrechtsgesetz" (laws I detest in this form and strongly oppose because they can strangle free speech, research and fair and open business competition), these bad laws can actually help us in prohibiting anybody in those countries to use any means to decode our encoded email, as our webpages are copyright-protected work and any tool to decode our copy-protection on this work (however simple or stupid this encoding might be), here namely the email, is illegal and can be prosecuted. Cute! ;-)

Why yet another email obfuscator tool?

1st I wanted a platform-independent solution (i.e. it should work with Linux, Windows, MacOS etc.). 2nd I was not content with the JavaScript Encoders I found. One actually had an endless if/else-chain for all the letters + ciphers to encode them, an other one only provided decimal code for a javascript-generated link. Others did not encode some characters. 3rd I wanted to refresh my JavaScript knowledge (not having written much lately).

I wanted the resulting code to work without JavaScript. In fact, it even works with non-graphical browsers. I checked with elinks, w3m and lynx as well as with standard graphical browsers, namely Mozilla 1.x/Netscape 6.x, Opera 6.x, Internet Exploder 5.x.