U2F Zero is an open source USB security token for two-factor authentication, designed for affordability, durability, and secure implementation.
U2F USB token optimized for physical security, affordability, and style
This tool is used to provide strong two-factor authentication (2FA) for online accounts supporting U2F, such as Google, GitHub, and Duo. It is ideal for security-conscious users who want a customizable, hardware-based authentication token that can be built and maintained independently. Developers and hobbyists can also use it to build their own secure authentication devices.
U2F Zero is no longer maintained and has been superseded by the Solo open source FIDO2 token, which offers enhanced security and easier customization. Users should consider migrating to FIDO2 tokens for future-proof authentication. The security level is comparable to modern car keys and while secret keys cannot be read or duplicated easily, side-channel attacks remain a theoretical risk for well-equipped adversaries with physical access.
Order the 8 SMT parts listed in the parts list
Purchase PCBs costing approximately $1.13 to $3.5 each
Obtain a compatible programmer (e.g., Silicon Labs DEBUGADPTR1-USB)
Assemble the components on the PCB following the build guide
Program the assembled token using the recommended programmer
Refer to the wiki for detailed building instructions and parts sourcing