Each week, it seems, there is a new announcement of a data breach of some sort. Jimmy John’s and Home Depot are just two of the recent hacks that gave thieves access to personal information. Each time it happens, we try to figure out how to protect ourselves, but the truth is, it doesn’t take a large-scale data breach to get your personal information.

While most of us know we need to keep passwords and personal details protected, we usually don’t think about usernames. Email, social media and a range of other online services all require some type of username and, depending on your choices, you may be helping criminals gain access to the private details of your life.

Cyber thieves use a technique called “doxing” said Shaun Murphy, CEO of PrivateGiant, a tech firm dedicated to online security. By combing the Web for little bits of information, they compile an entire profile of an individual. Then they use the information for identity theft or other scams.

“People do not realize that if they do something as benign as posting a comment on a public page with a username like CrazyShaunOrlando, those two pieces of information are enough detail for a criminal to exploit,” he said. A good cyber thief could use the information to find your home address, how much you paid for your home, where your kids go to school and more.

Here are some of the mistakes Murphy said people make when creating usernames online. Read on, and if you’re guilty, make a change:

  • Having one username across multiple accounts. Just like passwords, recycling usernames is a bad idea. It leaves an easy trail for criminals to follow.
  • Using all or part of your name. We're probably all guilty of this, but while using your name as a username makes it easy for friends and business associates to find you, criminals will have an easy time doing the same.
  • Revealing your location, birthday or other important numbers. Using the city you live in or your hometown in a username helps criminals narrow their search for your personal details. The same goes for your birthday. Since both types of information may also be used for security purposes, putting it out there in your username can make it easier to crack the codes to your accounts.
  • Linking a username to an email address. It is common to link your username with an email address, but anyone can test combinations of your username with popular email providers to figure out your email address, then uncover any accounts where you've used that email address to create a profile. Instead, use an altered version of your email address to sign up for websites and create an entirely different username.