A simple self-contained demo server supporting multiple devices per user. The central part is the Resource class.

1. Clone

git clone https://github.com/Yubico/java-u2flib-server.git

2. Run

./gradlew run

3. Try it out

Since U2F requires a HTTPS connection, this demo server uses a dummy certificate. This will cause your browser to show a warning, which it is safe to bypass.


  1. Why do I get error code 2?

    You are accessing the server using a URL that does not match the server’s App ID. The App ID is set to https://localhost:8443 by default, but you can change this in the Resource class.