Column and dozen bets both cover exactly 12 of the 36 numbered pockets on a roulette wheel. Neither covers the zero. Placing one chip on either bet type means the player is active on 12 specific numbers and inactive on the remaining 25, which includes zero on a single-zero wheel. Both pay 2 to 1.
How do column and dozen selections differ in structure?
A betting grid at https://crypto.games/ arranges numbers in two distinct groupings, and column and dozen bets reflect these two different geometric structures. Column bets follow the vertical layout of the grid. Three columns run from top to bottom, each containing 12 numbers.
- Left column covers 1, 4, 7, 10, 13, 16, 19, 22, 25, 28, 31, and 34.
- The middle column covers 2, 5, 8, 11, 14, 17, 20, 23, 26, 29, 32, and 35.
- Right column covers 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, and 36.
Numbers in each column are not consecutive on the wheel itself; they are consecutive in terms of grid position, meaning every third number from the sequence falls in the same column.
Dozen bets follow horizontal segmentation. First dozen covers 1 through 12. The second dozen covers 13 through 24. The third dozen covers 25 through 36. These are consecutive number ranges, which makes them visually simple to read on the layout, but produces a different distribution of wheel positions compared to column groupings.
Groupings on the wheel
Column numbers and dozen numbers map to different physical sections of the wheel. On a standard single-zero European wheel, the numbered pockets are not arranged in sequence. Consecutive numbers on the layout are spread around the wheel’s circumference rather than clustered together. Column groupings tend to produce more dispersed wheel coverage because every third number from the full sequence is pulled into the same column. Dozen groupings concentrate on consecutive number ranges, which do cluster somewhat more in specific arcs of the wheel depending on the wheel’s physical number sequence. Neither grouping produces genuinely uniform wheel coverage. Both cover exactly 12 of 37 pockets, and the payout is 2 to 1 regardless of which column or dozen is selected.
Payout and edge on third-coverage bets
A 2-to-1 payout on a 12-number bet follows the same formula as all other roulette bets. Covering 12 pockets leaves 25 uncovered on a 37-pocket wheel, including zero. Payout is calculated as 36 divided by 12, minus one, which gives 2 to 1. Staking 1,000 satoshis on a winning column or dozen returns 3,000 satoshis: 2,000 satoshis profit plus the stake back. Win probability for a column or dozen bet sits at 12 in 37, approximately 32.43 per cent per spin. Over 37 spins, a player expects to win approximately 12 times and lose approximately 25 times. Winning 12 times at 2 to 1 on a one-unit stake recovers 36 units from 37 spent. House retains one unit across that cycle, preserving the 2.70 per cent edge.
Combining columns and dozens
Players sometimes place chips on both a column and a dozen simultaneously. Where those two selections overlap, any number in the overlap zone produces two winning chips rather than one. Where they do not overlap, hitting one selection loses the chip on the other.
- The first dozen and the left column share 1, 4, 7, and 10 as overlap numbers.
- First dozen and middle column share 2, 5, 8, and 11.
- First dozen and right column share 3, 6, 9, and 12.
Overlap zones always contain exactly four numbers because two independent 12-number sets drawn from 36 share 4 numbers when selected from different geometric groupings across the same pool. Knowing the overlap count allows a player to calculate expected double-hit frequency before placing both bets in the same round.