Suguru — The Adjacency Experiment
Fill each cage of size N with the digits 1 to N. No two identical digits may touch — not even diagonally.
Suguru
6×6 grid. Small cages. Half the cells given. Learn the rules.
Standard play. Timer runs. Hints available.
What is suguru?
Suguru is a number-placement puzzle created by Japanese puzzle designer Naoki Inaba. The name comes from the Japanese word suguru (すぐる), meaning “to excel.” You might also see it called “number blocks” in English puzzle books or “tectonics” in Dutch and Belgian publications. The puzzle itself is the same regardless of the name.
The grid is divided into irregularly shaped cages. Each cage of N cells gets the digits 1 through N, one per cell. A 3-cell cage holds {1, 2, 3}. A single-cell cage is always 1. The second rule: no two cells that share an edge or corner can hold the same digit. That diagonal adjacency constraint is what gives Suguru its particular character. Unlike Sudoku, there are no row, column, or box constraints. Everything comes from cage membership and the 8-way adjacency rule.
Suguru is a popular fixture in UK newspapers. The Times and The Telegraph both run regular Suguru columns. If you have done the Suguru in your morning paper and want more, you are in the right place. We have 1,500 puzzles across five difficulty levels, from 6×6 grids for beginners to 14×14 grids certified solvable by logic alone.
How suguru works
Two rules. First: each cage of N cells must contain exactly the digits 1 through N. Second: no two adjacent cells (horizontally, vertically, or diagonally) may hold the same digit.
Tap a cell to select it, then tap a number to place it. Bold outlines show cage boundaries. When you select a cell, its cage and its 8 adjacent cells highlight so you can see the constraint zone. Use notes mode to track candidate digits. The auto-candidates feature computes which digits remain valid based on both cage membership and adjacency. If you get stuck, the hint system identifies a solvable cell and explains the technique behind it.
For the full rules with worked examples, see the rules page.
Play modes
Classic
Timer runs up. Up to 3 hints. Undo available. The default way to play.
Timed Trial
Beat the countdown. Time limit scales with grid size: 3 min for 6×6, 35 min for 14×14.
Challenge
No hints. No undo. Every digit placement is permanent.
Choose your difficulty
Suguru tips and strategies
Technique by technique, beginner to advanced.
1-cell cages first
A single-cell cage is always 1. Fill these immediately. They also block every adjacent cell from containing a 1, which narrows candidates across the board right from the start. Two-cell cages always hold 1 and 2, though you still need adjacency to figure out which cell gets which.
Small cage priority
Two-cell cages ({1, 2}) and three-cell cages ({1, 2, 3}) have limited candidates. Their adjacency effects spread fast. Start with the smallest cages and work outward.
Adjacency elimination
Every cell touches up to 8 neighbours (horizontally, vertically, and diagonally). If a neighbour already holds a digit, eliminate that digit from the cell's candidate list. For cells at cage boundaries, adjacency elimination often narrows candidates faster than cage constraints alone, because the cell interacts with digits from multiple cages.
Naked and hidden singles
A naked single is a cell with exactly one candidate left after elimination. Place it immediately. A hidden single is a digit that can only go in one cell within its cage, even though that cell has multiple candidates. Both techniques chain: placing one digit triggers new eliminations that create more singles.
Cage completion
When N minus 1 cells of an N-cell cage are filled, the remaining cell must contain the missing number from 1..N. Check this after every placement.
Cross-cage propagation
Adjacent cages share border cells. Placing a digit in one cage eliminates it from adjacent cells in the neighbouring cage, which can force placements further away. On larger grids, these chain reactions can ripple across the entire board.
Track this by maintaining full candidate lists. When you eliminate a candidate, re-check the affected cell's cage for hidden singles. Systematic re-checking is what separates solvers who get stuck from solvers who don't.