Boggle is a word game designed by Allan Turoff and trademarked by Parker Brothers and Hasbro. The game is played using a grid of lettered dice, in which players attempt to find words in sequences of adjacent letters.
The game begins by shaking a covered tray of sixteen cubic dice. Each die has a different letter printed on each of its sides. The dice settle into a four by four tray so that only the top letter of each cube is visible. After they have settled into the grid, a three-minute timer is started and all players simultaneously begin the main phase of play.
Each player searches for words that can be constructed from the letters of sequentially adjacent cubes, where "adjacent" cubes are those horizontally, vertically or diagonally neighboring. Words must be at least three letters long, may include singular and plural (or other derived forms) separately, but may not use the same letter cube more than once per word. Each player records all the words he or she finds by writing on a private sheet of paper. After three minutes have elapsed, all players must stop writing and the game enters the scoring phase.
In the scoring phase, each player reads off his or her list of discovered words. If two or more players wrote the same word, it is removed from all players' lists. Any player may challenge the validity of a word, in which case a previously nominated dictionary is used to verify or refute it. For all words remaining after duplicates have been eliminated, points are awarded based on the length of the word. The winner is the player whose point total is highest, with any ties typically broken by count of long words.
One cube is printed with Qu. This is because Q is virtually always followed by U in English words (see exceptions), and if there were a Q in Boggle, it would be unusable if a U did not, by chance, appear next to it. For the purposes of scoring Qu counts as two letters: squid would score two points (for a five-letter word) despite being formed from a chain of only four cubes.
The North American National Scrabble Association publishes the Official Scrabble Players Dictionary (OSPD), which is also suitable for Boggle. This dictionary includes all variant forms of words up to eight letters in length. A puzzle book entitled 100 Boggle Puzzles (Improve Your Game) offering 100 game positions was published in the UK in 2003 but is no longer in print.
Different versions of Boggle have varying distributions of letters. For example, a more modern version (with a blue box) in the UK has easier letters, such as only one "K", but an older version (with a yellow box, from 1986) has two "K"s and a generally more awkward letter distribution.
Using the sixteen cubes in a standard Boggle set, the list of longest words that can be formed includes Inconsequentially, Quadricentennials, and Sesquicentennials, all seventeen letter words made possible by Q and U appearing on the same face of one cube.
Big Boggle, later marketed as Boggle Master and Boggle Deluxe, featured a 5×5 tray, and disallowed 3-letter words. Some editions of the Big Boggle set included an adapter which could convert the larger grid into a standard 4×4 Boggle grid. In the United Kingdom, Hasbro UK currently markets Super Boggle, which features both the 4x4 and 5x5 grid and an electronic timer which flashes to indicate the start and finish. Despite the game's popularity in North America, no version of Boggle offering a 5x5 grid is currently marketed outside Europe.
Other obsolete Boggle variants include:
In the Philippines, a similar game which was first distributed in 1978 and is still in circulation up to the present is the game "Word Factory." The game was first patented in the Philippines, and is currently being manufactured and distributed to selected retailers by the Philippines-based game manufacturer, 13 P.M. Enterprises. Word Factory was a variation on the version of Boggle as it existed in 1978: using a 5x5 grid instead of a 4x4 one, and using plastic dice instead of wooden ones. At present, the game is being marketed to other countries, targeting mostly migrant Filipino families.
Unlike Scrabble, there is no national or international governing or rule-making body for Boggle competition and no official tournament regulations exist.