A hidden number is waiting to be cracked, read the positional feedback and the math-property tells, then deduce it before your guesses run out.
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How to play
Enter a guess and read the reply: a 'locked' peg means a correct digit in the correct spot, and a 'loose' peg means a correct digit in the wrong spot. Unlock property clues, facts about the secret like parity, divisibility or digit sums, to narrow the field without spending a guess. Identify the exact number before you exhaust your limited guesses.
Locked = right digit, right position; loose = right digit, wrong position.
Reveal a property clue any time, it costs a little score but no guess.
You have a limited number of guesses per case.
Cross-reference clues with peg feedback to corner the answer.
Game modes
Daily: the same case for everyone, in 3-digit, 4-digit, or 4-distinct-digit modes.
Practice: fresh random cases at your chosen difficulty.
Controls
Desktop: type digits and press Enter to submit; use 'Reveal clue' for a new tell.
Phone & tablet: tap the on-screen number pad to enter digits, ⌫ to delete, Guess to submit.
Tips & strategy
Spend an early clue or two, a divisibility fact often eliminates more numbers than a guess.
Track which digits are confirmed present but misplaced, then test new positions for them.
Solve quickly with few clues; both time and clue use lower your score.
What you'll learn
Number Detective sharpens mental math and number sense by combining guess-and-feedback deduction with real clues about a hidden number's properties.
Skills: number properties (primes, factors, parity), logical deduction, mental arithmetic
Best for: roughly grades 5–8 (ages 10–14)
For parents & teachers: blends logic and number theory into a satisfying daily puzzle.
About Number Detective
Number Detective is an original, free browser deduction game that fuses positional guess feedback with genuine number-theory clues to sharpen mental math. Play instantly, no install.
A free, original browser game on PlayPendium. No download, no install.
