What are trackers?
Definition
Trackers are bits of code on a website, in an app or on a device that record what you do online, such as the pages you visit, so companies can recognize you and build a profile.
- Category
- Privacy
- Also called
- trackers, internet trackers, web tracker, tracking cookie
- Last updated
The FTC lists the main ways this works. Websites can use a cookie or pixel to identify you even after you leave the site. They can use device fingerprinting, which relies on your browser's unique settings and configuration instead of a stored file. On phones, advertisers can use a unique advertising identifier to follow what you do across apps.
The FTC also separates two kinds. First-party tracking is the site you're on remembering you. Third-party trackers belong to other companies the site lets in, and the FTC says they can follow you across most websites you visit. That's how you can look at a pair of shoes on one site and see them in an ad somewhere else.
The data is useful to advertisers, and it also flows to data brokers, who combine it with records like your name, address and phone number. The more places you're tracked, the richer the profile about you.
Tracking isn't always sinister. A shop cart that remembers your items uses a cookie. The problem is the quiet, cross-site kind you didn't agree to and can't easily see.
Tracker vs. related terms
- A cookie is one common way to track. A tracker is the broader idea, which includes pixels, fingerprinting and ad IDs.
- Spyware is software that secretly watches you on your device. Trackers mostly work through sites and apps you chose to use.
- A keylogger records what you type, which is far more invasive.
How to protect yourself
- 1
Choose cookie options
When a site shows a cookie notice, the FTC says the choices often let you allow only cookies that are necessary for the site to work. Pick that.
- 2
Use an ad blocker
Ad blockers can stop some pixels and trackers. The FTC cautions that they don't necessarily block all tracking, so combine them with the next steps.
- 3
Adjust browser and phone privacy settings
You can block personalized advertising, restrict location sharing and stop websites from seeing your browsing history. On a phone, reset or turn off the advertising identifier.
- 4
Clear cookies and identifiers
Delete cookies now and then, and uninstall apps you don't use.
- 5
Cut down what trackers can connect to you
Serus finds where your address and phone number are listed and removes them, so a tracking profile has less to attach to.
See where your personal data is exposed
Serus finds it on data brokers and people-search sites and removes it.
Frequently asked
Are trackers the same as cookies?
Cookies are one kind of tracker. The FTC also describes pixels, device fingerprinting and advertising identifiers as ways to track people.
How do I know if a website is tracking me?
Most sites that use third-party tracking show a cookie notice. A browser extension or your browser's privacy report can list the trackers on a page.
Can I stop all online tracking?
Not completely. Blockers and settings reduce it, but they don't catch everything. The aim is to cut the amount that gets linked to you.
Is tracking legal?
Often yes, but laws like the GDPR and CCPA put rules on it, such as requiring a notice or consent in some places. The rules depend on where you live.
Sources
Something wrong or out of date? Tell us and we'll re-check it.