Incognito browser: What it really means

Firefox calls it private browsing, Chrome calls it incognito mode. Both let you browse the web without saving your browsing history.

What Incognito/Private Mode Does

Incognito or private mode keeps your browsing history private. That’s it.

What Incognito/Private Mode Doesn’t Do

A 2018 survey of 460 internet users by the University of Chicago found that there are a lot of misconceptions out there about private browsing or incognito mode. It won’t protect you from viruses or malware. It won’t keep your internet service provider (ISP) from seeing where you’ve been online. It won’t stop websites from seeing your physical location. And any bookmarks you save while in private browsing or incognito mode won’t disappear when you switch it off.

Why go private/incognito?

Just because you’re using private browsing mode doesn’t mean you’re up to something nefarious. Perhaps you want to keep your work and personal life separate. You might share a computer or device and you don’t want your siblings snooping. You could be shopping for a gift and you don’t want anything to spoil the surprise. Or maybe you just want to limit the amount of data companies collect about you and you value privacy. Incognito or private browsing mode is made for any of these scenarios.

Web Tracking

A lot of sites keep track of your browsing activity. Most do it to understand if you’re interested in purchasing a product or clicking on an article. They can also do it to help make their sites easier to use. But almost all tracking is done to serve you ads.

Online ads are customized based on your browsing. Been searching for a new pair of sandals? “Shoe Store X” has a great deal for you. The company knows where you’ve been because they dropped a bit of code into your browser called a cookie. The cookie tracks you, and so do Shoe Store X ads.


Cookies were first used to customize websites, keep track of shopping carts, and maintain online account security, but today most are used to help companies serve targeted ads.

Here’s how it works: You visit a site, an advertiser leaves a cookie on your browser. The cookie is your unique ID. Your information is stored in the cloud along with that ID. That can include which sites you visited, how long you visited them, what you clicked on, your language preferences and more.

Cookies also help advertisers deliver ads in your social media feeds. Social sites have their own tracking schemes and they’re far more robust. They can track every click, post, and comment. In addition, cookies can report what you’ve been doing online to a social site, which is how some ads follow you into social media.

Going Incognito

So you’ve decided to keep to yourself online, to go incognito or enter private browsing mode. What does that mean? In Firefox, Private Browsing deletes cookie data when you close the browser window and doesn’t track your browsing data. It also blocks tracking cookies by default. Finally, it won’t remember any files you download, but those files will still be on your computer.

In Chrome, incognito mode does the same thing. In either case, your actions could be visible to the websites you visit, your employer or school, or your internet service provider (ISP). Also, if you sign into any accounts, your browsing activity may be saved to that account. And chances are if you’re using Chrome, you’ll be logged into your Google account.

Firefox Tracking Protection

Firefox goes beyond private browsing with Tracking Protection. It stops companies from following you around the web. It uses a list of tracking sites compiled by Whenever a cookie tries to reach a site on the list, Tracking Protection blocks it.

Firefox Multi-Account Containers

The Firefox Multi-Account Containers add-on isn’t technically a form of private browsing or tracking protection, but it can help keep companies from knowing everything you do online. It lets you open fresh, cookie-free tabs that can be used for different accounts—personal, work, shopping, etc. That means you can use Multi-Account Containers to open several Google accounts at once without any overlap. Most trackers won’t associate the different accounts, keeping your work life separate from your personal life online. Some more advanced trackers, however, can and will track you across different accounts, so beware.

Is Incognito/Private Mode Really Private?

Incognito or private mode will keep your local browsing private, but it won’t stop your ISP, school, or employer from seeing where you’ve been online. In fact, your ISP has access to all your browsing activity pretty much no matter what you do.

You can, however, use a Virtual Private Network (VPN) service. VPN services route traffic through remote servers, so it looks like you’re browsing from another location or multiple locations. VPN providers can track where you’ve been online, though, so it’s good to find a company you can trust to either delete or lock up your browsing activity. VPNs won’t block third-party cookies from advertisers, but those cookies won’t be able to identify your location accurately, making it difficult or impossible for ad trackers to be effective.

Tor Browser can truly mask your online activity. It bounces traffic through multiple servers around the globe, making it difficult to track that traffic. The website you visit really has no idea where you are, only the approximate location of the last server your request was routed through. But again, even Tor proxy won’t stop third-party advertisers from installing cookies in your browser. Tor Browser deletes all cookies when closed. People can also start a new session in Tor Browser to clear them as well.

Incognito: TL:DR

Incognito mode keeps your browser history private, and that’s pretty much it. If you want more privacy, you’ll need to add Tracking Protection and maybe even browse through a Virtual Private Network (VPN) service. Incognito mode can’t.

Take control of your browser.