Address munging

Address munging is the practice of disguising an e-mail address to prevent it from being automatically collected by unsolicited bulk e-mail providers. Address munging is intended to disguise an e-mail address in a way that prevents computer software from seeing the real address, or even any address at all, but still allows a human reader to reconstruct the original and contact the author: an email address such as, "no-one@example.com", becomes "no-one at example dot com", for instance.

Any e-mail address posted in public is likely to be automatically collected by computer software used by bulk emailers (a process known as e-mail address scavenging). Addresses posted on webpages, Usenet or chat rooms are particularly vulnerable to this. Private e-mail sent between individuals is highly unlikely to be collected, but e-mail sent to a mailing list that is archived and made available via the web, or passed onto a Usenet news server and made public, may eventually be scanned and collected.

Disguising addresses makes it more difficult for people to send e-mail to each other. Many see it as an attempt to fix a symptom rather than solving the real problem of e-mail spam, at the expense of causing problems for innocent users. In addition, there are e-mail address harvesters who have found ways to read the munged email addresses.

The use of address munging on Usenet is contrary to the recommendations of RFC 1036 governing the format of Usenet posts, which requires a valid e-mail address be supplied in the From: field of the post. In practice, few people follow this recommendation strictly.

Disguising e-mail addresses in a systematic manner (for example, user[at]domain[dot]com) offers little protection. For example, such addresses can be revealed through a simple Google Search.

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