Device Fingerprint
Device fingerprinting is a process used to identify a device or browser by determining which technology, such as the Operating System (OS) and browser plugins along with other active settings, are present. Unlike website cookies that are stored on a user’s device, device fingerprints are stored server-side.
Device fingerprinting is used to track users and determine if they are unique or a known visitor. This method gives webmasters an important insight into who is visiting their site but comes at the cost of user privacy.
How device fingerprinting works
When a user visits a website, a device fingerprint tracker – usually a piece of JavaScript – collects all relevant information about their device, f.ex. their browser version, operation system, language settings, and the device’s IP address fingerprint.
What device fingerprinting is used for
Because device fingerprinting doesn’t provide reliable data, companies treat it as a backup method of tracking when cookies cannot be used.
It is mostly used for advertising and marketing purposes to target specific audiences.
For example, if your device fingerprint was identified as a new visitor, an advertisement could be displayed about a deal or sale that can only be used once.
An alternative use for device fingerprinting is to determine if someone has visited a website before without using cookies. This information can be used to prove that the user is unique and not a repeat visitor.
Device fingerprinting also enables companies to collect information on how users browse through their websites. For example, they may want to know where users are having trouble viewing certain content on their site or which visitors like certain pages better than others. They may also find this type of data useful in optimizing how search engines view their websites in search results.
Frequently asked questions about device fingerprinting
- How is device fingerprinting different from cookies? Cookies are stored locally on a visitor’s device and contain information about the user such as preferences or shopping cart information. Fingerprinting, however, stores data about the devices used to visit a website server-side and uses it for statistics purposes.
- Device fingerprinting will not work if I delete my cookies – how is it still able to track me? As mentioned above, fingerprints can be stored while using other tracking methods. In addition, most browsers automatically set new cookies every time you visit a website (which includes first-party sites like Google). These cookies do not have an expiration date but can be deleted at any time by the user or manually through browser settings. As long as you are visiting websites through these cookies, your browser will be tracked.
- How can I prevent device fingerprinting? Because device fingerprint tracking is server-side, users should make sure to use private browsing and delete all cookies in-between visits on different browsers or devices. It is also important to always have the latest updates of the installed plugins, software, and operating systems on your device to ensure you are using up-to-date security patches for all applications. Also, enable encryption on any wireless network used to access the internet (also called WPA2). This prevents surveillance devices from stealing data wirelessly as it travels from the computer to an Internet access point.