Obfuscating Email Addresses

Spammers often accumulate email addresses to which they send spam by using "harvesters , aka "email spiders". These are programs that spammers, or people from whom spammers buy lists of email addresses, use to search webpages for email addresses.

So, if you place an email address such as spamtrap01@moonpoint.com on a webpage, that address is likely to be found by such harvesters/spiders and will subsequently receive a lot of spam. Since, it is often necessary to place an email address on a webpage, a technique for obfuscating or hiding the email address in such a way that a human can make use of it, but it doesn't appear to be an email address to one of those email address harvesters should be used when placing email address on webpages.

One simple way to obfuscate the email address is to use the Cascading Style Sheets (CSS) display:none property. E.g., I could use the following:

spamtrap02@<span style="display:none">null</span>moonpoint.com

A human would see the following for the address as you do when you view the page without looking at its source code:


The "null" wouldn't be visible to a human reading the page, so the email address would be easily readable, but an email harvester program would see the "null" following the "@", making the email address invalid for it.


  1. E-mail address harvesting
    Wikipedia, the free encyclopedia
  2. Email Spiders
    Mail Msg
  3. Cascading Style Sheets (CSS) Wikipedia, the free encyclopedia

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