Arduino Psychic




Introduction: Arduino Psychic

This is a magic trick done using two Arduinos.

One Arduino is a random# generator, the other Arduino will identify a random # chosen by the audience.

Please watch the video. It's easier shown than explained. :-(


  • Any two Arduinos (I used two Arduino Nanos)
  • Any two or more digit 7-segment display. Sketch is coded for common anode, but it would be simple to modify the sketch for common cathode.
  • Fourteen 220 ohm resistors
  • Two momentary push button switches
  • One numeric keypad
  • Two breadboards and a handful of jumper wires

Step 1: Build the Randomizer

Wire up the first Arduino as shown in schematic above.

Upload this sketch to this Arduino.

Step 2: Build the Psychic

Wire up the second Arduino as shown in the schematic above.

Upload this sketch to this second Arduino.

Step 3: The Secret

You can build both of the circuits above and they will work together without requiring you to understand how it works.

However, if you learn how it works, you'll be able to use just the Randomizer and guess the random # chosen by your audience, or you could just use the Psychic to have him identify a random#.

This video explains the secret of how the trick works.

Battery Powered Contest

Participated in the
Battery Powered Contest

Be the First to Share


    • Big and Small Contest

      Big and Small Contest
    • Make It Bridge

      Make It Bridge
    • For the Home Contest

      For the Home Contest



    2 years ago on Step 3

    This is easy, after you stored a number, you will get no more random
    numbers but calculated numbers, the second psychic calculates your
    strored number from your input numbers


    Reply 2 years ago

    Had I started the project with two Arduinos, I probably would have taken a similar approach to what you suggested. However, I started with one Arduino replacing a deck of cards with numbers. The psychic was me. I don't know about you, but I can't do binary math as well as an Arduino :-) So, I came up with a different solution that even a six year old could handle. He/she would only have to do ONE simple subtraction to identify the secret#.