How to play Number Nibbles
from your first board to X-wings and chains
The rules
Fill every square so each row, column and 3×3 box holds the digits 1 to 9 exactly once. Tap a square, then a number. Or tap a number first to arm it, then paint it into square after square.
This row already holds every digit but one, so the empty square can only be a 7. Sudoku people call that a naked single, and it is the move you will make most.
Pencil marks ✏️
Pencil marks jot small maybe-numbers in a square while you think. Place a real digit nearby and the matching marks rub themselves out.
Candy hints that teach 🍬
A candy hint shows its working. Instead of quietly filling a square, it washes the row, column or box that proves the digit, so the trick sticks for next time. Lavender is the square in question; sky is the evidence.
Teacher depth 🎓 sets how much sudoku theory a candy may use before it simply hands you the digit.
The technique ladder
| Just answers 🍬 | no teaching, the candy quietly fills the square in |
| The basics 🐣 | singles, locked candidates, and pairs, triples and quads |
| Clever tricks 🦊 | X-wings, swordfish, colouring, XY and W-wings, empty rectangles, finned X-wings and unique rectangles |
| Chains 🔗 | jellyfish, finned big fish, X-chains, WXYZ-wings and XY-chains |
| Everything 🧙 | the lot, up to grouped chains and full alternating inference chains |
Difficulty flavours 🌶️
Every tier promises exactly what it can ask of you, and never sneaks in more. No board ever needs a guess: all six yield to pure logic, and the candy can teach every technique they use.
| Gentle 🐣 | singles only. Every square falls to "only one number fits" or "only one home left" |
| Tasty 🌈 | leaner boards, plus the occasional locked candidate to spot |
| Spicy 🌶️ | locked candidates and naked or hidden pairs do the heavy lifting |
| Fiery 🔥 | real patterns arrive: X-wings, colouring and XY-wings |
| Mighty 🐉 | the deep shelf: W-wings, swordfish, empty rectangles, finned fish and unique rectangles. Never a chain |
| Legendary 🦄 | chain country: X-chains, WXYZ-wings, XY-chains and alternating chains |
Playing together 🎉
Host a party and friends join with the code. Team puts everyone on one shared board with three shared hearts. Versus deals the very same puzzle to each phone: first to finish wins, and three slips puts you out.
Candy hints sit parties out; in a team your friends are the hints!
The daily challenge 🗓️
One shared puzzle a day, gentle on Monday and fearsome by Sunday. Fill the whole calendar for a perfect month.
Getting stuck?
Look for a square with only one possible digit, or a digit with only one home left in its row, column or box. Gentle boards fall to those two moves alone. The harder tiers are built so they will not, which is what the candy is for.
Questions
Is Number Nibbles free?
Yes. There are no ads and no accounts either; open the page and play.
Do I need to know the fancy techniques?
No. Gentle boards fall to singles alone, and the candy hints teach the rest when you are ready for spicier tiers.
Is it really never guesswork?
Really. Every board is built so pure logic finishes it, all the way up to Legendary.