Introducing Code Grid, a New Number Logic Puzzle on Puzzle Lair

We just added a new puzzle type to Puzzle Lair, and it brings a fresh kind of deduction to the site. Say hello to Code Grid, a number logic puzzle for players who enjoy careful clue reading, inventory tracking, and row by column reasoning.

What Is Code Grid?

Code Grid starts with a visible grid of digits. Your job is to fill a separate answer grid using the same digits, but rearranged into the hidden solution.

Each row and column has clue marks that compare the visible source grid to the hidden answer. The marks tell you how many digits are exact, misplaced, or absent.

The rules:

• Fill every answer cell with a digit from the source grid.
• Use each digit from the source grid exactly once.
• A filled dot means one digit is exact, correct digit, correct position.
• A hollow dot means one digit is misplaced, correct digit, different position.
• An X means one digit from the source line is absent from that answer line.
• Clue marks are unordered, so they tell you the count, not which specific cells they describe.

That last rule is where Code Grid starts to get interesting. A row clue might tell you that two digits belong in that row, but not where they go. A column clue might rule out a digit entirely. The puzzle becomes a process of narrowing possibilities, tracking the shared digit inventory, and finding the only arrangement that satisfies every clue at once.

How to Solve It

Start by comparing each source row and column to its clue. A line with no absent marks is especially useful, because every digit from that source line appears somewhere in the matching answer line. A line with several absent marks can be just as helpful, because it tells you which digits are not allowed there.

Then look for intersections. If a row can only use certain digits and a column can only use certain digits, the cell where they meet may have only one possible value. Medium and hard puzzles also reward pencil notes, since you may need to track several candidates before the grid starts to open up.

The digit inventory matters too. If a digit has already been used up, it cannot appear anywhere else. If a clue says a digit must appear in a line and there is only one place left for it to go, that placement can unlock the next chain of deductions.

Why We Built It

Code Grid has a different solving rhythm from the other number puzzles on Puzzle Lair. It is not about arithmetic, and the digits are not values to calculate with. They are symbols that need to be arranged perfectly.

We wanted a puzzle that feels compact and approachable at first, but gets deeper as the board grows. Easy puzzles give you a quick introduction on a 3x3 grid. Medium and hard puzzles expand the logic with larger grids, more digits, more duplicates, and more opportunities for satisfying deduction.

Try It Now

Code Grid is live on Puzzle Lair today, with easy, medium, and hard difficulties to work through. It supports both Check mode and Instant mode, so you can solve at your own pace or get immediate feedback as you play.

Code Grid is launching in beta while we tune the puzzle generation and difficulty balance, so if you run into anything unexpected while playing, we would love to hear about it. The hard puzzles have a limited number since they take a long time to generate, so hopefully you don't get through them too quick!

Head to the puzzle catalog and give Code Grid a try. If you like logic puzzles that reward patient clue reading and careful elimination, this one should give you plenty to think about.