What are trackers on websites?
Definition
Website trackers are cookies, pixels and similar technologies that a site places on or reads from your device to recognize you and record what you do, often for advertising or analytics.
- Category
- Privacy
- Also called
- web trackers, online trackers, tracking technologies
- Last updated
The UK's data regulator, the ICO, uses the umbrella term storage and access technologies. Its guidance covers cookies, tracking pixels, device fingerprinting and similar tools, and says the rules reach any technology that stores information on your device or reads information stored there. That includes mobile apps and embedded software kits, not just web pages.
How they work
A tracker lets a site or a third party recognize your browser again. A cookie stores an identifier on your device. A pixel is a tiny image that reports a visit when your browser loads it. Fingerprinting works without storing anything, by reading details of your device that tend to be unique.
A typical case: you read an article, and an ad company's tracker on the page notes it. Later, on a different site that carries the same tracker, you see ads for something related.
Not all trackers are the same
The ICO says that strictly necessary technologies, such as remembering a shopping basket, are exempt from consent. Advertising purposes are not exempt. Under UK rules, organisations should tell you about the trackers, explain what they do and get your consent before setting them. Continuing to browse does not count as consent.
Trackers vs. cookies
A cookie is one kind of tracker. Trackers also include pixels and fingerprinting, which cookie settings alone do not always stop.
How to protect yourself
- 1
Say no on the cookie banner
Choose reject or manage settings rather than accept all. Where the law requires consent, a clear refusal should be honored.
- 2
Use browser privacy settings
Block third-party cookies and turn on your browser's tracking protection. Settings help, though they don't stop every method, such as fingerprinting.
- 3
Clear cookies regularly
Deleting cookies resets the identifiers sites hold for you.
- 4
Check app permissions
Trackers also run in mobile apps. Limit tracking permissions and location access in your phone settings.
- 5
Remove the profiles built from your data
Trackers feed data to advertisers and brokers. Serus finds where your personal data is listed and removes it where it can be taken down.
See where your personal data is exposed
Serus finds it on data brokers and people-search sites and removes it.
Frequently asked
Are website trackers legal?
In the UK, the ICO's rules require organisations to tell you about trackers and get your consent, except for strictly necessary ones. Other countries have their own rules, so what is allowed depends on where you live.
Can trackers see my passwords?
Ordinary tracking cookies and pixels record things like pages visited, not passwords. Malicious scripts are a different problem.
Does private browsing stop trackers?
Not fully. Private mode usually deletes cookies when you close the window, but sites can still see your activity during the session.
Sources
- ico.org.uk/for-organisations/direct-marketing-and-privacy-and-electronic-communications/guidance-on-the-use-of-storage-and-access-technologies/what-are-storage-and-access-technologies/
- ico.org.uk/for-organisations/direct-marketing-and-privacy-and-electronic-communications/guide-to-pecr/cookies-and-similar-technologies/
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