pixeline

This plugin provides an unobtrusive yet efficient protection against email harvesters / spambots. Here is a <a href="https://pixeline.be/blog/email-protector-demo-4258.html" rel="nofollow ugc">demo</a>.
Post/page authors may write email addresses in their article in the usual format (“john@doe.com”) without exposing them to spam email harvesters. The plugin takes care of the obfuscation, implementing a graceful degradation technique focusing on usability so as to protect your email addresses from harvesters while keeping them usable to your human visitors.
The plugin replaces any email address found in posts, pages, comments and excerpts, and replace them by a bit of html markup that should deceive most email harvesters: <code>john(replace the parenthesis by @)doe.com</code>. 
If javascript is available, it will display a clickable link and display the original email to the human user. Maximum usability, maximum protection.
Please <a href="https://wordpress.org/extend/plugins/pixelines-email-protector/" rel="ugc">rate the plugin</a> if you like it.
<h3>Usage</h3>
Write your email addresses inside your posts and pages as usual. When the plugin is activated, it will replace them by a human-readable html string that explains how to deduce the email address, and if javascript is available (99.9% of the time), the original email address will be displayed as a clickable mailto: link. For example: 
 Hello john@doe.com. How are you today? 
will become 
 John( replace these parenthesis by @ )doe.com.
Additionally, you can specify what the mailto: link should look like by sticking a parenthesis inside of which you put the visible link text, like this:
<pre><code>Hello john@doe.com(John Doe). How are you today?
</code></pre>
will become 
 John( replace these parenthesis by @ )doe.com.
<h4>inside a theme</h4>
If you need to protect emails inside your Theme’s files (like the footer.php for example), you can use the function safe_email() like this:
<pre><code> echo safe_email('you@domain.com'); <h3>Contribute</h3>
</code></pre>
Github repo: https://github.com/pixeline/pixeline-email-protector

Pixeline's Email Protector

Write email addresses without worrying about spambots and email harvesters.

michael_greenberg

PHPEnkoder is a port of the excellent <a href="http://hivelogic.com/enkoder" rel="nofollow ugc">Hivelogic 
Enkoder</a> to PHP and, more specifically, 
to WordPress. It is used to display text in a way that users can see 
and bots can’t.
The encoding system is directly and unabashedly stolen from the 
BSD-licensed source of Hivelogic Enkoder, which works by randomly 
encoding a piece of text and sending to the browser self-evaluating 
Javascript that will generate the original text. This works in two 
ways: first, a bot must first have a fairly complete Javascript 
implementation (in particular, it must have <code>eval</code>); second, the 
decoding process can be made arbitrarily computationally 
intensive. This is similar to the idea of charging computational 
payments to send e-mail, only this is actually implemented.
By default, PHPEnkoder scrambles e-mails in plaintext and in <code>mailto:</code> 
links. It additionally provides a shortcode for manual scrambling, 
used like so: <code>[enkode text="shown to non-JS browsers"]this will be 
scrambled[/enkode]</code>.

PHPEnkoder

Encodes mailto: links and e-mail addresses with JavaScript to stifle webcrawlers.  Automatically turns plaintext e-mails into (enkoded) links.

Pixeline's Email Protector vs PHPEnkoder