Keeping Michael Guessing since 2026!
Ken's Key Exchange
Create a shared secret number while communicating in an open room
Everyone may know
Both phones use the same public starting numbers.
- Prime number
- 10007
- Base number
- 5
- 1 Choose
- 2 Exchange
- 3 Reveal
Turn your screen away for this step
Choose your private number
Pick a whole number from 2 to 10000. Do not show or say this number to anyone!
Your screen is now safe to share
Exchange public numbers
Your phone mixed the public base with your private number. Tell the room the result below—this number is not a secret.
Say: “My public number is .”
Compare screens
You created a shared secret
If both people entered the public numbers correctly, both phones will show the same result.
What just happened?
You combined the other person's public number with your own private number. They performed the mirror-image calculation, so you both arrived at the same result without exchanging either private number.
What the room was allowed to know:
- Public prime: 10007
- Public base: 5
- Your public number:
- Their public number: