66: the 6 combos
To count 66, pick 2 of the 4 sixes: 4 x 3 / 2 = 6 pairings.
Every 66 you can be dealt is one of these 6 holdings. They are listed once each, higher card first.
How cards you can see change the count
Known cards cannot be in an opponent's hand. For 66, the table lists the combos left after one card of each rank is out of play.
| Known card | 66 combos left |
|---|---|
| Ace | 6 |
| King | 6 |
| Queen | 6 |
| Jack | 6 |
| Ten | 6 |
| Nine | 6 |
| Eight | 6 |
| Seven | 6 |
| Six | 3 |
| Five | 6 |
| Four | 6 |
| Three | 6 |
| Two | 6 |
A six you can see leaves 3 of 6, so 50% of the combos are gone. Any card of a different rank leaves all 6 combos in play.
When the board is paired
A pair on the board uses up two of the four cards of its rank. The 66 combos that survive are in the table, one row per rank.
| Board pair | 66 combos left |
|---|---|
| Aces | 6 |
| Kings | 6 |
| Queens | 6 |
| Jacks | 6 |
| Tens | 6 |
| Nines | 6 |
| Eights | 6 |
| Sevens | 6 |
| Sixes | 1 |
| Fives | 6 |
| Fours | 6 |
| Threes | 6 |
| Twos | 6 |
Pairing sixes on the board cuts 66 to 1 combo. Every other paired board leaves the full 6.
A worked example
Take a hand of a six and a two. Your opponent then holds one of 1,225 possible hands, and 3 of them are 66. That is 0.24%, or 1 in 408, instead of the 0.49% (1 in 204) you get when your cards do not block it.
How strong is 66?
Rank 17 of 169 belongs to 66, inside the top 30 classes, on 63.29% equity against a random hand. Equity here is wins plus half of the ties across all boards.
Add 66 to every hand ranked above it and you hold 110 of the 1,326 two-card hands, 8.30% of all deals.
66 against ranges of hands
A range is a list of hands, and equity against it weights each hand by its live combos. For 66 the five ranges give 25.63% against the top 5 percent (60 combos), 40.24% against the top 10 percent (130 combos), 48.44% against the top 20 percent (264 combos), 52.51% against the top 30 percent (386 combos) and 56.31% against the top 50 percent (658 combos).
| Opponent range | Combos in range | 66 equity |
|---|---|---|
| Top 5 percent | 60 | 25.63% |
| Top 10 percent | 130 | 40.24% |
| Top 20 percent | 264 | 48.44% |
| Top 30 percent | 386 | 52.51% |
| Top 50 percent | 658 | 56.31% |
The line sits between the top 20 and top 30 percent: 66 is behind the narrower range and ahead of the wider one.
Holding 66 removes some premium combos from an opponent's reach: of the 130 in the top 10 percent, an average of 125.00 remain. That is 5.00 combos fewer than the 130 an opponent has before you look.
Hands next to 66
A one-place difference in rank can be a large or small gap in a direct matchup. 66 has 50.92% equity against KQs, the hand ranked number 16: it wins 50.68% of boards, ties 0.47% and loses 48.85%. It is the favorite in that matchup. 66 has 53.24% equity against A9s, the hand ranked number 18: it wins 53.03% of boards, ties 0.42% and loses 46.55%. It is the favorite in that matchup.
Because both cards of 66 have the same rank, there is no suited version of it. The 13 pairs are 78 combos in all, 5.88% of the 1,326 hands.
Questions about 66 combos
- How many combos of 66 are there?
- 6 combos, which is 0.45% of the 1,326 two-card starting hands, so you are dealt 66 about 1 time in 221.0.
- How many 66 combos are left if I hold a six?
- 3 combos of 66 remain out of 6. With a two as your other card, an opponent has it about 1 time in 408.
- Which hands rank next to 66?
- KQs ranks number 16, just above 66, and 66 has 50.92% equity against it. A9s ranks number 18, just below, and 66 has 53.24% equity against it.
How this was computed
Every 66 combo was listed from the 1,326 two-card holdings. For each blocker or board-pair row, the combos that contain a visible card were dropped and the rest were counted.
The rank and equity figures use our matchup table, which counts all 1,712,304 boards for each pair of classes. Ties are halves, and range matchups are weighted by live combos.
Source: GeorgeLiPoker's own count of the 52-card deck and its preflop matchup table.