Diffie - Hellman key exchange is a system to generate a shared secret over a public channel. This implementation is a demo, and not to be used with sincerity. But it does work and can be fun.
This is your half to sent to the other person:
Paste what they send to you below:
Then make your shared secret:
This is your shared secret, use it to derive other keys:
You can test this yourself by opening two browser windows and copying/pasting between them.