Gmail auto-aliasing, or yet another reason to signup for Gmail

I’ve been slowly updating all of my online accounts to use my new Gmail account. There are many things to love about Gmail (ease of use, labels, ginormous storage limits), but one of my favorite features is auto-aliasing.

Follow up:

Auto-aliasing for Dummies

First, some background. An e-mail alias is just another name for an existing e-mail account. It’s handy in situations where you want to have a bunch of different e-mail addresses, perhaps for business sake, but you don’t want to have to deal with the hassle of logging into or maintaining multiple e-mail accounts. So for instance, you might have a personal e-mail account like, but then have a bunch of other e-mail addresses like and, both of which you set up to aliases of the first. All three are valid, deliverable addresses as far as your e-mail server is concerned, but all three go to the same mail box, and thus mail to any of the three addresses can be picked up under the single “” inbox.

(Note to SMTP nerds: I realize that this is probably not a completely accurate technical description, but it will do for our purposes here.)

Ye Olde E-mail Aliasing Task

On most mail services that I’ve used in the past, setting up an alias is a time consuming process that must be done in advance. For me, it would usually involve logging into my hosting provider’s control panel, selecting the domain I want to manage, clicking the link to manage all of the domain’s e-mail accounts, clicking the link to manage the e-mail account I want to create the alias on, and finally entering the new alias. This usually took somewhere in the realm of 10-15 minutes depending on how slow the control panel was responding. Considering this, I usually avoided creating e-mail aliases.

Aliasing Made Easy with Gmail

Gmail’s auto-aliasing feature lets you create aliases just by specifying an alternate form of your address. For instance, if your Gmail address is usually, you could create an auto-alias just be using instead. (The technical term for this type of aliasing is Plus-addressing.) Gmail will ignore anything after the plus sign for delivery of e-mail, but you can still use the extra alias information to create filters, run searches, or, as I do, to find out what web services are selling your e-mail address to marketing agencies!

Alias Your Way to a Spam Free Inbox

Yup, now every time I enter my e-mail address into an online form I’ll use an auto-alias to help me identify the site that I used it on. Typically I’ll just use the web site name as the alias, such as If I start seeing a ton of spam to that address (which come to think of it is unlikely anyway given Gmail’s awesome spam filter) I can create a new filter to automatically delete any mail addressed to that alias, as well as cancel my account with the offending site, or at the very least write them a scathing passive aggressive note.

Web Developers Take Heed!

I’m about to get technical, so skip over this if you have no idea what a regular expression is…

One unfortunate obstacle to using Gmail’s auto-aliasing feature is that many web sites use e-mail address validation filters that mistakenly report addresses containing a plus sign as invalid. This is a side effect of the fact that most e-mail validation schemes typically rely on a basic regular expression pattern which can’t possibly test for all valid permutations of an e-mail address. If you’re going to use a filter to test for a valid e-mail address, all you can really do is make sure that there is an @ symbol, followed by domain name of at least two-characters, followed by a “dot”, and ending with a TLD of at least two-characters. Other than that, the only real way to test for a valid, deliverable e-mail address is to send it an e-mail and wait for a response.

A lay-persons conclusion

So, if you’re not using Gmail by now – why aren’t you? It’s free; It’s web-based so it’s available anywhere you have access to a browser; It’s secure (you can use an SSL connection for even more security); It has a great built-in zero-configuration spam filter (7715 spam messages caught to date with only a handful of false-positives); You can apply multiple labels to e-mail conversations to make it easy to find things later; It’s got a great search tool (it is a Google application after all); You can import mail from any other account that supports POP3 (which is most accounts, Hotmail excluded); and now you know all about how to use auto-aliasing for fun and profit!

As an added bonus

Oh, and if you use a Blackberry or other mobile phone+EBTKS device, you can download Gmail for your phone! Woot for checking Gmail from the road!

* This post was originally published on September 26, 2007 at

Code comes and goes. It gets refactored and deleted. Lessons taught to other developers live on. They survive longer than any feature or project.