Number Link
Number Link is a Japanese puzzle in which you have to connect squares together in order to fill a grid.
Fans of Sudoku, Kakuro, Hashi and the like are sure to find this logic puzzle a refreshing challenge!
The timhalbert.com daily Number Link service has been discontinued as of May 2006. The puzzles themselves will remain available for download and for online play, but for the time being, no new puzzles will be created.
The main reason for this is due to a technical design issue with most of our puzzles. Our rules stipulate that all squares must be filled in a puzzle, and in most cases, this has led to most puzzles having a unique solution. Without this stipulation, however, there are tens more solutions to most of these puzzles. Traditional Number Link designers never need to make this stipulation: their puzzles are carefully crafted so that they have only one actual solution, and all the squares happen to be filled. We don't count as 'traditionalists' in this case! It is a puzzle, certainly, but not "Number Link", which we've called it all this time. We feel we've been quite naughty, so there we go: it's over.
Thanks for all your support! ~ Tim
Third-generation Number Link
Each pair of numbers can be joined together by a Number Link: a single, continuous path of matching coloured squares.
No overlaps or blocks of colour are allowed and all squares in the puzzle must be coloured in.
 |
 |
 |
 |
 |
5x5 puzzle |
No overlaps |
No blocks |
All squares |
The solution |
Hints and tips
There is only one correct solution to each puzzle.
Approach each one with an element of logic - don't play by guesswork alone!
If a square can only contain one possible colour, fill it in.
If you try a route and it doesn't work, there may only be one other way around the problem.
Try starting from the outside edge, working your way slowly into the centre.
Older puzzles
Puzzles from October 2005 to February 2006 were built in Microsoft Excel.
These puzzles are all still playable, but you will have to familarise yourself with the Excel interface before you begin.
Clicking and dragging won't work.
Second-generation Number Link (January 2nd to February 25th, 2006)
First-generation Number Link (October 13th to December 25th, 2006)
Second-generation rules
Each pair of numbers can be joined together by a path of matching coloured squares (i.e. a Number Link).
Rules
Each pair of numbers can be joined together by a Number Link: a single, continuous path of matching coloured squares.
No overlaps or blocks of colour are allowed and all squares in the puzzle must be coloured in.
Tips (solving in Excel)
Save the puzzle to your computer first. In Excel, drop down the Fill Color box on the toolbar, and drag it down to float it next to your puzzle. This will help you change the colours faster. Use the CTRL key to select several squares at once.
» Still having trouble? Click here.
Tips (solving on paper)
You can print out the puzzle if you prefer to do it by hand. It will fit on one piece of landscape A4 - just open it up in Excel and hit Print. Instead of colouring in the grid, most people choose to draw lines through the squares to represent a path. Remember, the same path cannot appear in more than two adjacent squares.
Number Link variants
 |
Samurai: Modelled on the popular Samurai Sudoku variant. Each of the four corners of the centre grid overlap with four other grids placed around the edge. The overlapping corner squares share the same colour. January 2006 |
 |
Bridges: A large grid with all sorts of twists and turns. Some paths cross over/under each other: these are bridges, and they allow overlapping paths (even of the same colour). February 2006 |
This week's most recent Number Link are available for download on the front page.
Second-generation Number Link
If you spot any mistakes in these puzzles, please let us know.
» 26.12 - Monday 8 by 8 |
» 2.1 - Monday 8 by 8 |
» 9.1 - Monday 8 by 8 |
» 16.1 - Monday 8 by 8 |
» 23.1 - Monday 8 by 8 |
» 30.1 - Monday 8 by 8 |
» 6.2 - Monday 8 by 8 |
» 13.2 - Monday 8 by 8 |
» 20.2 - Monday 8 by 8 JAVA |
* This puzzle was later found to be "cooked" (it broke the rules or had multiple solutions).
First-generation rules
- No overlaps are allowed.
- All squares in the puzzle must be coloured in.
- If you see 2 portals (sets of dotted lines on the edge of the puzzle), then a line can 'wrap' through them.
- A square is allowed to touch a maximum of 2 other squares of the same colour (i.e. no blocks of colour).
- Squares separated by a dotted line do not count as adjacent (in which case the last rule doesn't apply).
- Paths cannot cross the edge of the puzzle, walls, or over the sides of dotted line portals.
First-generation Number Link
Advent Calendar
For the 2005 Christmas season, Daily Number Link took the form of an Advent Calendar.
» Click here to download Answer Sheet (32KB, .xls format)
» Click here to see updated Advent Calendar (38KB, .xls format)
» Click here to see the Advent Calendar solutions (44KB, .xls format)
If you spot any mistakes in these puzzles, please let us know.
The much-fabled Number Link book
The prologue:
Sudoku, eh? All you hear is "Sudoku this, Sudoku that". Most of us are admittedly growing a little tired of Sudoku. The world really doesn't need a new Japanese logic puzzle at the moment, and Number Link is it!
Like most Japanese logic puzzles, the average onlooker thinks it's all about maths, and no, they don't want to have a go for fear of looking like a complete gimp.
Number Link guarantees you absolutely no maths whatsoever. All the puzzles will challenge you to link up pairs of numbers together, nothing more. Looking objectively at everything you see is the key to success.
You do not need to use the Maxwell-Boltzmann kinetic theory of gas equation to work out the solution to any of the puzzles, except perhaps the really, really hard ones.
This book will help you discover for yourself the true beauty of Number Link. You'll learn tips and tricks on how to solve puzzles faster, and you'll be tested to the limit with increasingly meaner levels of difficulty as we progress through the book.
You'll also learn how to milk a goat, teach yourself to play the guitar with your toes, and formulate the best way to go about attending a funeral wearing nothing but a plasma belt.
You may also soon discover that the last paragraph is a filthy, heinous lie. Hopefully not too soon, though, because, out of sheer disappointment, you'd probably then proceed to take the book back to the shop for a full refund, rendering me destitute and forcing me to eat gravel for the rest of my life.
So let's get cracking!
All puzzles © Tim Halbert, all rights reserved.