Canadian and American bingo cards are 5 × 5 grids of numbers only; dual daub or double-action cards have two numbers in each square. Each space in the grid contains a number, except for the centre square, which is considered filled. The highest number used is 75. The columns are headed with the letters of the word BINGO, and the letter is called with the number — for example, B-10, I-25, N-40, G-55, O-70. Numbers 1 to 15 are assigned to the B column, 16 to 30 to the I column, 31 to 45 to the N column, 46 to 60 to the G column, and 61 to 75 to the O column.
In the United Kingdom and Australia bingo cards have three rows and nine columns. Five squares in each row contain numbers ranging from 1 to 90 and the rest are blank. The numbers are usually called quickly, so players rarely play more than one book (six cards). A bingo book (a set of six cards) contains all the numbers from 1 to 90, fifteen numbers on each card, five numbers in each row. The first column contains single numbers, the second tens, the third twenties, and so on. Number 90 is placed in the ninth column along with the eighties.
Each card has a unique serial number to permit quick verification by computer.
Calculating the total number of possible combinations yeilds the result that there exists 552,446,4557,061,129,000,000,000,000 possible BINGO cards, 4,976,640,000 of which would have the same twenty four numbers, but in a different arrangement.
If we presume that there are six billion people in the world today, that means that there are 92,0557,412,343,521,400 cards for each and every person in the world.
If you could print a million cards per second, it would take 17,505,972,382,599.7 years to print every possible BINGO card,