As the the company behind the world's biggest search engine, video sharing platform, email provider and mobile operating system, Google knows a lot of information about its users.
Plenty of people search or browse YouTube without being signed in, meaning the data Google has access to is anonymised. It knows how you behave on its sites, but the information can't be traced back to you.
That all changes if you're signed in to a Google account, the most convenient way to access personalised information across all your devices. Google is open about the data it collects, insisting that 'your privacy is protected by responsible data practices. What's more, there are several steps you can take to control or limit what the company has access to.
Here's everything you need to know.
How well does Google know me?
Google used to be only a search engine. Remember that? Almost certainly you still use Google Search, a lot. And Google collects a lot of data about the searches you make, as it says a lot about you. Sign in and head over to Google and view the search history that Google holds about you. You can also see your YouTube search history here.
More prosaic but also critical basic information can be found in your account details. Sign in and head to the Google account About page to see the basic data you gave to Google. Head to Dashboard and you can see records of an array of Google tools, and your activity with them. We'll click into a couple of these further along, but suffice to say that this is an important dashboard for finding out what Google knows about you.
This is the basic data Google is likely to hold about you:
- Your name, gender and date of birth
- Your email addresses
- Your phone numbers
- Where you live
- Where you work
- Website you've visited
- Searches you made on Google Search
- Your ad preferences (more below)
- Your interests
- Places you've visited around the world
- Your YouTube search history and recently watched videos
- What you've said to the Google Assistant, including via smart speakers
How can I see my Google activity?
With ease, thanks to a relatively new tool that gives you a timeline of events and the ability to delete those events individually, should you want to.
Log into your account and head to the My Activity page. You should see a page which looks like this:
Scroll down and you'll find a chronological list of all your activity, including searches, map browsing, YouTube and more. You can search for a specific item, or filter by date/product.
The information that appears here will depend on the permissions you've allowed. Here, Google warns that some activity from the same day may not yet appear.
How do I remove items?
Next to each activity and date, you'll see an 'X'. Click it, then 'Delete' to confirm.
In the top-right of the image above, you'll see a drop-down menu also marked 'Delete'. Clicking this lets you delete all activity from the last hour, day or a custom date range, as well as everything associated with a specific app.
From the same site, you can also completely turn off 'Web & app activity' or 'YouTube history'. Just click the relevant buttons from the top of the page and choose 'Turn off'.
However, you might not feel the need to delete large amounts of your activity history - it's only available to you and not shared with others.
What does Google think you're interested in?
The principle reason Google tracks all this data about you is so that it can more successfully target you with advertising, in order to fund the services you access for free. For most people, this is a worthwhile sacrifice in order to access Google's services without paying a penny.
But it is interesting to find out just what Google thinks it knows about you, and how it uses that to target ads your way. Sign in and head to Settings. You will see what Google considers to be your gender and age, as well as your interests.
If you haven't told the truth when entering basic information - or you've never entered it - you might find it amusing that Google has your age or gender completely wrong.
It's interesting to see the range of things Google thinks you're interested in, particularly on a personal account. From the same page, you can also opt-out of adverts related to a specific interest identified, or turn off personalisation altogether.
You can also opt out of allowing website owners to track you via Google Analytics. Simply head over to the Google Analytics opt out page, where you'll find an add-on available for Chrome, Safari, Firefox and Microsoft Edge.
Where does Google think you've been?
One of the options available from the Google Settings Dashboard outlined above, is the ability to find out where Google thinks you have been. You can head there directly at Location History. This is typically tracked using the GPS in your phone: chances are even if you don't use an Android phone you'll still be signed into your Google account on an iPhone.
How to stop Google collecting location information
From the same page, select 'Manage location history' (as indicated above), then click 'Turn off'.
A pop-up with information will appear. Scroll down to the bottom and click 'Pause'
What devices, apps and services have access to your Google data?
In many ways this is the most important test of all. One of the benefits of Android is that it lets you know what permissions are required by each app you install on Android.
But you encounter lots of different Google apps and services on multiple devices. This page lists the devices and services, and what access they have. Click on a listed device and you can see further details and the opportunity to revoke, on the righthand side.
To revoke permission, just click the relevant app and choose 'Remove Access'.
How can I change which Google information is visible to others?
With Google's About Me tool. This shows what's publicly visible, and you can click the pen icon to edit anything to remove it or change it.
It is well worth using Google's Privacy Checkup tool as well. Head to the Dashboard and click on the Get Started link. Now just go through the list and pick the options you're happy with.