Physical Interfaces: USB, NFC, Apple Lightning®

We refer to the ways that a computer, phone, tablet, etc. can connect with a YubiKey as the physical interfaces.

USB

All of the models in the YubiKey 5 Series and Yubico Security Key Series provide a USB 2.0 interface, regardless of the form factor of the USB connector. The YubiKey presents itself as a USB composite device in addition to each individual USB interface.

USB A or USB C or both connectors are supported.

The USB PID and iProduct string changes depending on which of the USB interfaces are enabled. They are described in the YubiKey USB ID Values Guide.

For more information, see Understanding the USB Interfaces.

Apple Lightning®

The YubiKey 5Ci presents itself as an Apple iOS peripheral. It is able to interact with:

  • Any iOS app using the Yubico YubiKey iOS SDK.
  • Any app input data field through the touch-triggered OTP.
  • Any WebAuthn-compliant application (starting in iOS 13). This includes the Safari browser.

When connecting the YubiKey 5Ci through Lightning®, the interfaces enabled setting is common to both USB-C and Lightning®. Enabling or disabling an interface applies to both connections.

Note

Developers: Enabling apps within iOS to use advanced protocols that send and receive information from the YubiKey 5Ci requires that you:

The USB and iProduct strings that are displayed when connecting through Lightning® or USB are specific to the connection type. They are described in the YubiKey USB ID Values guide.

NFC

The Near Field Communication (NFC)-capable hardware security keys from Yubico provide an NFC wireless interface and a USB interface. These models include the RFID standard specific to the ISO/IEC 14443-A and ISO/IEC 14443-4 NFC format. RFID implementations not included in the listed ISO standards are not supported.

Yubico NFC YubiKeys:

  • YubiKey 5 and YubiKey 5C
  • YubiKey 5 FIPS and YubiKey 5C FIPS
  • YubiKey 5 Enhanced PIN and YubiKey 5C Enhanced PIN
  • Security Key and Security Key C

For an example of the NDEF URI format, click the YubiKey NFC demo link. The <OTP> value is replaced with the OTP generated by the YubiKey.

For Apple iPhone devices, iPhone 7 or newer is required. Background tag reading is supported in the iPhone XS and newer.

For operations that require a touch, touch the YubiKey within the first 20 seconds of the operation request to succeed.

When using a desktop NFC reader:

  • To help prevent unintended access, a YubiKey placed on a desktop NFC reader might power down unless the NFC reader power-cycles. This prevents the YubiKey from powering down.
  • To regain connectivity with an NFC reader, remove the YubiKey from the reader and reposition it on the reader.

Click for Yubico Support.