ƒ RULEZZLE

TODAY'S RULEZZLE

Today’s puzzle

Find a five-digit input that reaches the target.

TARGET OUTPUT —
Enter a five-digit number

Loading today’s puzzle…

HOW TO PLAY

Find today’s hidden rule.

  1. Enter all five digits, then select Try → to see the output produced by the hidden function.
  2. Use each output to work out the rule and find an input that reaches the target.
  3. You have ten guesses. A new function arrives every day.

Every digit position matters. Leading and trailing zeroes are preserved: 00042 and 42000 are different inputs.

The function might use maths, digit patterns, or something less obvious. After the game, you can choose whether to reveal the rule and an example solution.