Number Blocks is a gentle but clever number puzzle. The grid is split into blocks of different sizes; a block of 3 squares holds 1, 2 and 3, a block of 5 holds 1 to 5.
The twist: the same number can never be in two squares that touch, not even diagonally. That one rule links the blocks together and makes every puzzle solvable by logic.
Choose Sides only for a version where numbers may touch at corners — a little easier, and great for beginners.
Fill each block of n squares with the numbers 1 to n, so that no two touching squares hold the same number.
The full guide, with a worked example and common mistakes: How to play Number Blocks.
In that version, equal numbers may touch at a corner — only squares sharing a side must differ.
Yes — every puzzle here is checked to have exactly one solution.
Up to 5 or 6 squares, depending on the option you choose.
Open the Number Blocks Solver, draw the blocks, type the givens and press Solve.