Glossary
What is a device ID?
A device ID, or device identifier, is a value that lets a service recognise the same browser, phone or computer on a later visit. It can be stored on the device, as with a cookie or an advertising ID, or worked out from the traits the device reveals, as with a fingerprint. Fraud teams use device IDs to tell a returning device from a new one and to see how many accounts one device has touched.
Common types
- Cookie or local storage ID: simple, but cleared by the user or a private window.
- Advertising ID: set by the phone’s operating system and resettable by the user, meant for ad measurement.
- App install ID: created by an app on first launch, and lost when the app is reinstalled unless it is backed by the platform.
- Fingerprint-based ID: computed from the traits a browser or device reveals, with nothing stored.
Why it matters to an online business
Accounts, emails and phone numbers are cheap to create. A device is harder to replace. Knowing that ten sign-ups came from one device, or that a login comes from a device the account has never used, is more telling than any single field in the form.
What a device ID is not
It identifies a device, not a person. A family may share one computer and a person uses several devices. Treat it as one piece of evidence alongside your other checks. Collecting it should be disclosed in your privacy policy.
Where FingerPrint Checker fits
FingerPrint Checker gives every browser visitor and every Android, iOS and macOS app install a device ID that is computed and matched on our servers. Your backend reads it only from the decision call, and identifying a device is free.
Frequently asked questions
Is a device ID personal data?
It can be, depending on the law where your users live, because it can single out an individual device. Disclose it in your privacy policy and use it for a clear purpose such as fraud prevention.
Can a user reset a device ID?
Stored IDs can be cleared. IDs computed on the server from device traits are harder to reset, though a major change to the device can create a new one.
What is the difference between a device ID and a fingerprint?
A fingerprint is the set of traits. A device ID is the identifier derived from it, or stored on the device, that you can look up later.
Try it on your own sign-up flow
Every new account gets 2,000 free checks. No card required.