Simple Number Tools
Games

Can You Guess Random?

Tap 0 or 1 and try to be truly random. A simple predictor guesses your next tap from your past patterns - and usually beats 50%. See how unpredictable you can be.

Can You Guess Random?

Tap 0 or 1, again and again, trying to be completely random. Before each tap, the computer predicts what you will press - using only the patterns in your previous taps. Over 50 taps, can you keep it below 50%? (Most people cannot - we are surprisingly predictable.) You can also use the 0 and 1 keys.

People are bad at being random. Ask someone to type a long string of 0s and 1s “at random” and patterns creep in - they avoid long repeats, they alternate too evenly, they favor certain rhythms. This game turns that into a challenge: tap 0 or 1 over and over, trying to be truly unpredictable, while a simple predictor tries to call your next tap before you make it.

How to Play

  1. Press Start, then tap 0 or 1 (or use the 0 and 1 keys).
  2. Before each tap, the computer commits to a guess based only on the patterns in your previous taps.
  3. After 50 taps you see how often it guessed right. Pure chance is about 50% - the predictor usually does better. Your lowest (most random) score is saved.

How the Predictor Works

It keeps a short memory of what you tapped after each recent run of taps - say, “the last three were 0, 1, 1.” When that run shows up again, it bets you will do what you did last time. That is enough to catch the habits almost everyone falls into. Genuine randomness has no such habits, so holding it near 50% is genuinely hard.

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