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You may have heard the term "FIDO2 security key" in connection with signing in to your account. This article explains what a FIDO2 security key is and how it is used.
Detailed Information
A FIDO2 security key is a small physical device — similar in size to a USB flash drive — that you plug into your computer or tap to your phone to prove your identity when signing in. It is one option for multi-factor authentication (MFA), which adds a second step to the sign-in process to help keep your account secure.
How It Works
When you sign in, you enter your username and password as usual. If you are using a FIDO2 security key as your second factor, you will be prompted to insert the key into a USB port (or use NFC to tap it to your device) and press the button on the key. The key communicates with the website or app to confirm that it is really you signing in.
Why It's Considered Secure
FIDO2 security keys are considered one of the strongest forms of MFA because the key works only for the specific site you registered it with, making it highly resistant to phishing. Even if someone tricks you into visiting a fake login page, the key will not respond to it.
Common Devices
YubiKey is one of the most widely used FIDO2 security keys. Other manufacturers make compatible keys as well.
Environment
- All platforms (Windows, macOS, Linux, iOS, Android)
- Any service that supports FIDO2 / WebAuthn authentication