Overview
Device Fingerprinting returns two kinds of identifiers based on different hardware, browser, and network characteristics:- IDs
- Fingerprints
IDs
IDs are based on a cookie, and they are guaranteed to be unique. IDs are good for identifying good users returning to your site. However, they are easily changed by bad actors who clear their cookies or use private browsing (incognito mode).Fingerprints
Fingerprints are deterministically-generated hashes of various low-level signals. These do not depend on stateful storage or IP address, so they remain stable even in incognito mode or when a VPN is used. Fingerprints are usually stable for months or longer, including through routine browser updates. Rarely, a browser update changes low-level signals permanently, which results in new fingerprints. There are four different levels of fingerprints:- Visitor (most specific)
- Browser
- Hardware
- Network (least specific)
Table of different identifiers
This table outlines the distinct qualities of each identifier. For more details on different fingerprint characteristics and usage with our/rules endpoint, see Setting Rules.
Using Fingerprints & IDs
You can set rules based on specific fingerprints to customize the behavior for specific devices. Fingerprints can also be tied to other user data to associate known hardware sets, browsers, and other attributes with your user base.Examples
Invisible CAPTCHA
Add an invisible bot protection for a smooth user experience.
Prevent free trial abuse
Stop fake account creation abuse.
Block traffic by country
Use IP-based geographic filters for access control.
Remembered device
Add a remembered device flow.