Make your code

What this page does

Your browser generates an elliptic-curve key pair — P-256, through the browser's own Web Crypto implementation, not code we wrote. The public half becomes the short code you send your organizer. The private half is written into the part of a URL after the #, which browsers never send to a web server, and that URL is your keep link. Nothing you see on this page is transmitted by this site: the key is made here, shown here, and travels onward only in whatever you paste it into.

Your organizer sends you a link they cannot open. It is sealed to a key your own device generated and sent to nobody. There is exactly one moment we cannot protect: the draw itself runs in the organizer's browser, so an organizer watching with developer tools open at that instant sees the pairing. We cannot remove that moment without a server, and a server is what every other tool has. If you'd rather nobody had it, hand the draw to someone who isn't playing.

There is deliberately no passphrase on the keep link. Wrapping the private key under one and handing the wrapped blob to the organizer would put a permanent offline guessing target in the hands of the one person the mode exists to exclude, and it would mean printing a strength estimate this tool cannot honestly compute. A keep link is one more message in the same thread the sealed link will arrive in — which is a retention problem you can see and manage, rather than a cryptographic promise that quietly depends on how memorable your passphrase was.