To play, click on a cell and enter a digit. Once selected, arrow keys can be used to move around the canvas. Use keys 1-9, or A-Z for double digit values 10-35. Bold digits are the initial puzzle values; digits turn red if the rules of the game are violated. You can click on borders between cells to make a note of expected numeric separations, though no error checking is made. The canvas border will turn green if the grid is completed without error. You can also click on an existing number and "drag" it to other cells to overwrite their value with its value.

Enter puzzle code (1-0) or descriptor (see "Puzzles" tab):

The full set of rules for Fillomino can be found online. The simple description includes two basic rules. 1) The grid canvas is divided into a collection of number clusters, where each cluster has like-numbered numerical values (1-35) grouped in horizontally- and vertically-adjacent cells, and, when completed, contains the number of cells of the numerical value itself. For instance, a legal collection of '4' digits has four adjacent cells of any configuration. 2) Collections of like-numbered digits cannot border other collections of the same digit. For instance, a legal collection of 4-digits cannot border another collection of 4 digits. Put another way, a collection of 5 or more adjacent '4' digits is illegal. The canvas will indicate this with red-colored digits once the collection is in error. Similarly a collection that has no chance of growing as large as needed to make it of legal size turns that collection's digits red. You can type 'space' or 'backspace' to clear an entered digit, or you can click the "Undo" button on the bottom of the page. On the "Game Play" tab, select puzzle 0 to see a completed sample grid.

This playground was written using javascript and is available open source. More later.

Puzzles can be invoked by either a numerical entry from 1-0, or through a character description of the puzzle itself. The numbered puzzles are hand-crafted of varying difficulty, roughly easy to hard. To describe a puzzle, the character string must be of the form: "WxH:<descriptor>", where W is a number indicating the width of the grid, and H the height. The descriptor is a definition of the grid contents from left to right, then top to bottom. A dash '-' can indicate an empty cell. For easier description of sparse puzzles, letter values from 'a' to 'z' can indicate 1 to 26 empty cells, respectively. A dot '.' can be used as a separator, for example between rows. Cell contents for values greater than '9' should use capital 'A' to 'Z' for 10 through 35. An example descriptor is as follows: "6x10:--3---.b3c.12d.77a89A.f.f.b4b5.c321.Ce.CCc1".