How Safe Is Incognito Mode/Private Browsing, Really?

You might open a new browser window in Incognito Mode and think you’ve just vanished under a cloak of darkness with all your internetting perfectly hidden from the world. Sorry to burst your bubble, pal, but no. The various “private” options web browsers provide are not a panacea for your privacy concerns. In fact, you may be shocked to learn how little protection they actually provide from prying eyes, but there are still good reasons to use them. Today we’re going to dive into what these private browsing modes do, and what they don’t.

Do all browsers have a private mode?

All of the major web browsers out there have a private mode. In Chrome, it’s called Incognito Mode. Microsoft’s Explorer and Edge browsers both have “InPrivate” mode. For Firefox and Opera browsers, it’s called “Private Browsing.” Well, a rose by any other name would smell as… uh, insecure? Yeah, let’s go with that. There are subtle nuances between these different offerings, but they ultimately all pretty much do the same thing.

What it actually does

Simply put, these private viewing modes will hide your internet activity from others who might look at your actual computer. That is, family members, coworkers, roommates, and such. We’re talking about people with physical access to your computer. Incognito Mode and its ilk will not save the websites you visit, the info you might put into forms on those websites for autofill, or the cookies from those websites. For this reason, it’s good for:

• Searching for gifts when you don’t want a family member to see what you’re looking for
• Logging in to multiple email or social media accounts that only allow one user logged in at a time
• Searching for things that you don’t necessarily want showing up in your search history (as a journalist this happens a lot)
• Searching for airplane tickets, as some companies may change prices on you based on your search history
• Other things which you would rather not have autofill in your URL bar

What it doesn’t do

Unfortunately, the list of things private browsing modes don’t do is a lot longer. Most of them actually warn you of this when you first open a window, but this is generally ignored by people, so it’s worth spelling out here:

• It cannot hide your activity from your internet service provider. Your ISP can still monitor the sites you visit.
• That’s extra true if you happen to be internetting at work or at school. Your activity may still be tracked by the resident IT person or the institution’s provider. For this reason (and other obvious ones) you really shouldn’t be doing anything on your work/school computer that you want hidden.
• It doesn’t hide your activity from the websites you visit. The data you enter on those sites (the things you search for, the links you click, etc.) will probably still be monitored and recorded by those websites.
• It doesn’t mean your activity can’t be traced back to you. Even though cookies and browsing history will be deleted off your computer once you close the window, websites these days may have access to sophisticated tools such as browser fingerprinting, which can still allow them to link you to your real identity.

This all isn’t to say that private browsing is bad or useless, it’s just important to understand its limitations. If you really do need a more secure way to browse the web, there are tools that can help, like a VPN, which we’ll be getting into in future posts.