Note: This article lists the technical specifications of the Security Key NFC. If you're looking for setup instructions for your Security Key NFC, see https://www.yubico.com/start.
The Security Key NFC provides the FIDO2 application as well as the U2F application, and can communicate using near-field communication (NFC), allowing for greater flexibility.
Storage
| YubiKey Application | Firmware 5.7+ | Firmware 5.0 - 5.6 |
| FIDO2 | Up to 100 discoverable credentials (unlimited non-discoverable) | Up to 25 discoverable credentials (unlimited non-discoverable) |
| FIDO U2F | Unlimited credentials | Unlimited credentials |
Interface
The Security Key NFC uses a USB 2.0 interface as well as an NFC interface. All of the applications are available through both interfaces.
Applications
FIDO2
The FIDO2 application allows for secure single and multi-factor authentication, and can store up to 25 discoverable credentials (100 with firmware 5.7+). These credentials, which are protected by a PIN, enable passwordless login, where the YubiKey, unlocked by a PIN and authorized by touch, can log you in to your accounts without entering a username or password. For FIDO certification information, see YubiKey Hardware FIDO2 AAGUIDs.
USB Interface: FIDO
FIDO U2F
The U2F application can hold an unlimited number of U2F credentials.
USB Interface: FIDO
To find out if an application is compatible with the Security Key NFC, browse to the Works With YubiKey Catalog, and in YubiKey drop-down, select Security Key NFC to only display services that are compatible with it.
Physical Specifications
Form Factor
Connector: USB-A
Dimensions: 18mm x 45mm x 3.35mm
Weight: 3.6g
Temperatures
Operational range: 0 °C to 40 °C (32 °F to 104 °F)
Storage range: -20 °C to 85 °C (-4 °F to 185 °F)