What private browsing actually hides, and from whom

A private window hides your browsing from other people who use the same computer account. That is the feature. It gives the session a blank cookie jar, keeps the pages you visit out of your history, and throws away everything the session collected when you close it. Everything outside your own machine is untouched: your internet provider, the network you are on, the sites you visit and any monitoring software installed on the device all see precisely what they would have seen anyway. It is a local housekeeping tool that got a name which sounds like a cloak.

What a private window actually does

Opening one starts a separate session with its own storage. Concretely, five things happen.

• No cookies or site data are carried in from your normal browsing, so you start signed out of everything, even sites you are permanently logged into elsewhere.
• Cookies, site storage and cached files created during the session are kept only in memory for that session and discarded when it ends.
• Pages you open are not written to browsing history, and what you type into the address bar or a form is not saved for autofill.
• Permissions you grant, such as camera or location access for a site, normally last for the session only.
• Extensions are usually disabled in private windows unless you explicitly allow each one.

Two details catch people out. The session ends when you close the last private window, not the last tab, so leaving one open for a week keeps everything alive for a week. And saved passwords are generally still offered for filling, because those live in your profile, while new ones are not saved. If that sounds like the wrong trade for a borrowed machine, it is the reason passwords kept in a browser deserve their own decision.

What it does not do

Nothing about your connection changes. Your address is the same, so the site knows the same amount about where you are as always, which is not much but is not nothing either: what an address reveals is identical in both windows.

Name lookups still go to the same resolver, so whoever answers them still records which sites you asked for, exactly as described in the lookup that happens before every page. Your provider still sees which servers you connect to. Encryption covers the contents of the pages, not the fact of the connection, which is the same boundary the padlock draws in any window.

The site itself sees a visitor with your address, your screen size, your fonts and your browser build. If you sign in, it sees you by name. No browser feature can undo a username you typed yourself.

Files you download are written to disk and stay there after the window closes, even where the browser leaves them out of its download list. Bookmarks you add persist. And software already on the machine, whether monitoring installed by an employer or something malicious, records what it records regardless of which window you used.

Who can still see your browsing

The first row is the only one that says no, and even that comes with a footnote. It is a useful row. It is just a much smaller promise than the icon suggests.

Why it is not anonymity

Anonymity would mean a site cannot tell one visit from another. A private window fails that test because most modern recognition does not rely on anything stored in your browser.

Fingerprinting measures the device: screen dimensions, installed fonts, time zone, language, browser version, the precise way your graphics hardware renders a test image. Nothing is saved, so there is nothing for a private session to discard, and the same combination of values shows up in the private window as in the normal one. The mechanisms are set out in how tracking is actually assembled, and the short version is that a blank cookie jar defeats the oldest of four techniques.

Some browsers do add tracker blocking inside private windows, which helps a little. It is a separate feature that happens to be switched on there, not a property of privacy mode itself, and you can usually have the same protection in normal browsing by turning it on.

When private browsing is the right tool

It has real uses, all of them local.

• A shared or borrowed computer. A hotel desk, a library, a relative laptop. Sign in, do the thing, close the window, and your account is not left waiting for the next person.
• A second account on a site you are already signed into. Opening a private window is faster than logging out and back in twice.
• Seeing a page as a stranger would. Checking whether a link you shared actually works for people who are not logged in, or what a public profile looks like from outside.
• Keeping something off a shared machine history. Gift shopping, a surprise trip, a health question you would rather not have completed in the address bar next week.
• Testing. Anyone who builds or troubleshoots websites uses it constantly to get a clean session without destroying their own.

For anything you do repeatedly, separate browser profiles or container tabs are better than a private window, because they keep sessions apart permanently instead of throwing them away each time.

The myths worth retiring

It does not get you cheaper flights or hotels. Prices move with seats sold, demand and the fare class still available, and a repeated search often changes for reasons that have nothing to do with you. Where prices genuinely do vary, it is usually by country, currency or device type, none of which a private window changes, since your address and your device are exactly the same.

It does not hide anything from your employer. On a managed device, monitoring and certificate based inspection operate below the browser. On a company network, the network sees the traffic. Neither one asks which window you used.

It is not protection against malware or phishing. A malicious download is still a download, and a convincing fake login page still collects what you type into it.

It does not replace a VPN, and a VPN does not replace it. They solve different problems: one clears local traces, the other changes who sees your traffic on the way out. Both are worth understanding on their own terms, which is what the three things a VPN cannot do covers.

What to use depending on who you are hiding from

Pick by the observer, not by the feeling.

1. Other people in your home. A private window works. A separate user account on the computer, plus a device passcode, works better and permanently.
2. Your own other account. Use browser profiles or container tabs. They survive a restart and do not sign you out of anything.
3. The websites themselves. Stay signed out, run one content blocker, and accept that fingerprinting still narrows you down. Adding exotic extensions makes you more distinctive rather than less, which is also why the permission an extension holds deserves a second look.
4. The network you are on. Turn on encrypted name lookups and use a VPN when the network belongs to somebody else. That is the realistic answer to what is still risky on shared wifi.
5. Your employer, on their equipment. Nothing on their device will help. Use your own device on your own connection for anything personal.

The honest summary is that private browsing does one job well and is asked to do five it was never built for. Use it for the shared computer, close the window when you finish, and get your privacy from the layers that actually face outward.