2. What is a fingerprint?

Fingerprint is a combination of device and browser specifications used for unambiguous identification without the use of cookies. The term covers two similar but slightly different concepts – browser fingerprint and device fingerprint.

Browser fingerprint

This is a technique in which the site, via JavaScript and CSS, collects data about:

• browser type and version, operating system, User Agent;
• time zone, interface language, regional settings;
• installed codecs, plug-ins, fonts, extensions;
• screen configuration: resolution, color depth;
• rendering behavior (canvas, WebGL), audio API, CSS metrics.

These parameters are combined into a digital print that is almost unique. There are two methods of operation.

The Canvas fingerprinting method works by rendering an image. JavaScript reads the differences in GPU and drivers, creating records that are unchanged even when the cookie or IP is updated.

CSS-fingerprinting is a more stealthy method, works even when JavaScript is disabled, by utilizing the CSS processing peculiarities of different browsers.

Device fingerprint

It is broader in scope and includes hardware and network characteristics of the device. This includes unique component identifiers, battery data, processor performance, and TLS/TCP information. Such fingerprints are used to detect fraudulent activity, synthetic accounts, and phishing scenarios when conventional means are ineffective.

Why and by whom fingerprints are used

• Ad networks and marketers use fingerprinting to link user actions across sites and devices. This happens through indirect indications, even if cookies are disabled or deleted.
• Anti-fraud companies use fingerprinting to protect against bots and spoofing.
• Banks and financial platforms use device fingerprinting as an additional security factor. When logging in from a new device or non-standard configuration, the system may request a second factor or block the action.

How to reduce the risk of tracking

It is impossible to completely eliminate fingerprinting without the limitations of modern web technologies. But there are ways to reduce recognition:

1. Use browsers with protection. For example, 0DETECT browser. Also, Tor Browser standardizes fingerprinting across all users, blocks canvas and WebGL.
2. Install extensions. Privacy Badger, uBlock Origin, CanvasBlocker, and NoScript can block scripts or distort the fingerprint.
3. Disable JavaScript, WebGL, or canvas. Reduces the efficiency of fingerprint collection, but can disrupt many sites.

Use VPNs, Tor, proxies. Mask IP and some network attributes, interfering with fingerprint correlation.