GOOGLE'S Incognito Mode is a great way to hide your online antics – but there's a big hole that could leave you exposed.

A new study from Vanderbilt University reveals a sneaky way Google can see exactly what you've been looking at online.

The study investigated how Google collects info from you across devices (like Android or Chromebooks) and services (like Google, YouTube, and the Chrome web browser).

And it revealed something very surprising about Incognito Mode.

It emerged that Google can still record the websites you browse while in Incognito Mode on the Chrome browser, and link them to your identity.

This will come as a surprise to some users who thought the special setting protected them.

Incognito Mode is a setting on Chrome that prevents your web history from being stored.

It also won't store cookies – small files about you – that are linked to your identity.

If you're logged into Google, much of what you do online can be traced back to your personal account.

But if you switch Incognito Mode on, you'll only receive "anonymous" cookies, and Google won't be able to link your identity to your browsing habits.

Sadly, there's a catch.

If you log back into Google before leaving Incognito Mode, Google will be able to retroactively link your browsing data to your account.

That means Google could see information from before you logged in, but while you were in Incognito Mode – and link it to your Google identity.

This works by taking the previously anonymous cookies, and then associating them with your Google account.

The only way to get around this would be to only log into your Google account after you've left Incognito Mode.

"While such data is collected with user-anonymous identifiers, Google has the ability to connect this collected information with a user's personal credentials stored in their Google Account," the study explained.

Douglas Schmidt, a professor of computer science who authored the study, said the loophole is "not well understood by consumers".

"If you read the fine print on 'incognito' mode, it brings up a whole lot of disclaimers," said Schmidt, as quoted in a report by AdAge.

He said that Google collects "all the information necessary" to connect your browsing to your identity.

"It would give them a relative advantage to anyone else who can't do that correlation," he added.

The news comes just days after Google was exposed for spying on your real-world movements, even if you have its Location History setting turned off.

To stop Google tracking your location, you can follow our handy guide.

As far as Incognito Mode goes, it's also worth mentioning that while Incognito Mode stops Google Chrome from saving your browsing habits on your own computer, it won't protect you from outsiders seeing what you do online.

Anyone on your Wi-Fi network could potentially use special spy software to view what you're browsing, regardless of Incognito Mode.

And your employer will be able to use similar technology to see what you're browsing at work, too.

It's entirely possible that your employer logs every website you visit while at work.

Your internet service provider (so BT, Virgin, and so on) will also be able to see what you're doing online.

That means the police can also get access to what you view in Incognito Mode, simply by requesting that information from your internet provider.

The websites you're using will also be able to track that you're online on their page, too.

For instance, Google will know where you're browsing from, and what you're looking at

And if you log into a website, they'll also be able to keep track of information about you.

So when you log into Facebook in Incognito Mode, details about what you do on the site will be recorded – just the same as if you were using it in a normal web browser.

The key point is that Incognito Mode is not a great method of ensuring privacy, because it's still very easy to track what you're doing online.

It's only really useful for keeping websites out of your browsing history, or logging into a single website on multiple accounts in the same web browser.

We've asked Google for comment on this article and will update our story with any response.