mailto:for Spam Prevention
Summary: Prevent e-mail siphons from harvesting your e-mail addresses by separating the address from the Web page while still providing a way for users to click a link and have it open their local mailer.
If you don't know the problem with
mailto: links, read Why
no mailto?, by Jakob Nielsen.
This Redirect-mailto: trick reduces spam by separating e-mail addresses from
Web pages while still providing a way for the user to click an e-mail address
link and have it open their local mailer. Use a script that redirects to a
mailto: URI, similar to how you would redirect to a Web page
(for more complete protection, combine this trick with the a graphical
@ if you need to show the email address itself on the Web page):
|HTML Code||Rendered Link|
mailto: redirect, IE 5.5+ and Mozilla 5.0+ browsers may
change the browser window to a blank page as it opens the e-mail software
-- Opera and older versions of Netscape and IE handle the
redirect without drama. Regardless, hitting the back button returns you to
the page that you were on.
#!/usr/bin/perl -w # redirect-mailto.pl use CGI qw(:cgi); $user = param("u"); $domain = param("d"); print redirect( -URL => "mailto:$user\@$domain" );
<?php // redirect-mailto.php header("Location: mailto:$_GET[u]@$_GET[d]"); ?>
<% 'redirect-mailto.asp response.redirect("mailto:" & Request.QueryString("u") & "@" & Request.QueryString("d")) %>
Place this script in a directory such as
file to exclude obedient robots from crawling it and grabbing the output of
the link. You could even include some code that compares the user agent to
those listed in http://www.robotstxt.org/wc/active/all.txt,
and if it is a robot, return nothing.
Redirect mailto: for Spam Prevention by James Thornton