Nobody likes full email box, especially when you’re flooded with mail from companies you’ve never heard of. You don’t even know how your email got to these people. The answer is user lists shared between businesses, which is a business in itself. And the culprit: there’s a way to tell. A little trick in Gmail lets you find out who’s sharing your contact information with other companies.

The trick was created by journalist Yoni Heisler, from BGR.com. Here’s how it works: Whenever you log in or sign up for a service and enter your email address, add a plus sign (“+”) to the first part of the contact, along with the name of the app. Suppose, for example, you need to log in to the website of the bakery around the corner to order a roll. If your email is “[email protected]”, the field should be written as “[email protected]".

From then on, if the reader starts receiving a lot of spam emails, just look at which email it was sent to. If it was sent to your regular Gmail, the bakery is innocent. But if it comes with a +, it's because it was shared by the bakery.

The reason this trick works is because Gmail ignores letters placed between the “+” and “@” signs in the contact. So you can add any additional details between those characters and it’s the same.

Alternative form

But it’s not always possible to do this. In some services, the use of the plus sign in the email field is not allowed (we wonder if companies don’t already know about this trick). If this happens, add a period anywhere in your username. That is, instead of “[email protected]”, write the login as “fulano.siclano.souza” or “[email protected]”. It doesn't matter, distribute the points however you want. Just like the “+” sign, the gmail ignores dots in the username and handles incoming emails as if they weren't there. And find out who shared it.

You can benefit from this Gmail trick not only to sift through companies that share your contact information, but also to organize your inbox. Let’s say you’ve joined an online chess league and want to easily group all correspondence related to it. Simply create the address “[email protected]” and you will be able to find all emails related to the topic with a simple filtered search.

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