Bingo cards are flat pieces of cardboard or non-reusable paper which contain 25 squares arranged in five vertical and five horizontal rows; Dual dab, or "double-action" cards have two numbers in each square.

Each space in the grid contains a number, except for the center square, which is considered filled. The highest number used is 75.

The letters B, I, N, G, O are pre-printed above the five vertical columns, with one letter appearing above each column. The center space is marked "free."

The printed numbers on the card correspond to the following arrangement: 1 to 15 in the B column; 16 to 30 in the I column; 31 to 45 in the N column; 46 to 60 in the G column and 61 to 75 in the O column.

There are 552,446,474,061,128,648,601,600,000 (five hundred fifty-two septillion, four hundred forty-six sextillion, four hundred seventy-four quintillion, sixty-one quadrillion, one hundred twenty-eight trillion, six hundred forty-eight billion, six hundred one million, six hundred thousand) possible arrangements of the numbers on a bingo card.

The most chips one can place on a Bingo board without having a Bingo is 19, not counting the free space.

In order for this to happen, only one empty cell can reside in each row and each column, and at least one empty cell must be in each diagonal, for instance: