--- title: "66 vs A2s: preflop equity" url: "https://georgelipoker.com/equity/66-vs-a2s.md" canonical_url: "https://georgelipoker.com/equity/66-vs-a2s" last_updated: "2026-10-23" type: "reference" summary: "66 is a big favorite over A2s before the flop: 66.55% to 33.45% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/66-vs-qto.md", "https://georgelipoker.com/equity/66-vs-44.md", "https://georgelipoker.com/equity/a9s-vs-a2s.md"] --- # 66 vs A2s: preflop equity 66 is a big favorite over A2s before the flop: 66.55% to 33.45% equity, counted exactly over every board, with the split by flop type and suit. Averaged over every possible board, 66 is ahead of A2s by 33.10 points of equity, 66.55% to 33.45%. ## 66 against A2s: the numbers **Exact preflop results for 66 against A2s, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | 66 | 66.311 | 0.480 | 33.209 | 66.551 | | A2s | 33.209 | 0.480 | 66.311 | 33.449 | 66 and A2s are a pocket pair and a suited hand, in that order. One of the other hand's cards outranks the pair and one is below it, which makes this a closer race than a pair against two small cards. 66 is well ahead, and A2s needs a specific kind of board to catch up. Ties are 0.48% of the outcomes here; each tied board gives both hands half the pot. By strength against a random hand, 66 holds place 17 of 169 and A2s holds place 46. **Boards behind the percentages: 41,095,296 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | 66 | 27,251,000 | 197,000 | 13,647,000 | | A2s | 13,647,000 | 197,000 | 27,251,000 | The total is exact: 24 specific deals times 1,712,304 boards. The three counts are approximate, worked out from the percentages to five decimals and rounded to the nearest thousand. **66 against A2s read as odds** | Hand | Equity as odds (to 1) | Wins one deal in | Loses one deal in | Pot odds needed to call (to 1) | | --- | --- | --- | --- | --- | | 66 | 1.990 | 1.508 | 3.011 | 0.503 | | A2s | 0.503 | 3.011 | 1.508 | 1.990 | The last column is the smallest pot odds, written as a pot-to-call ratio, at which a call breaks even with this equity. ## Who is ahead on which flops If you know the kind of flop that came, the numbers shift: 66 holds 81.51% on low rainbow flops (nine high or lower) and 62.96% on monotone flops. 66 stays ahead on all five textures, but the swing between them is large, so how the flop looks matters a great deal. **66 against A2s by flop texture, in percent** | Flop | Share of flops | 66 wins | Ties | A2s wins | 66 equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 25.220 | 65.935 | 0.251 | 33.814 | 66.060 | | Rainbow, nine or lower | 5.689 | 81.100 | 0.820 | 18.080 | 81.510 | | Two-tone | 46.545 | 65.477 | 0.323 | 34.200 | 65.638 | | Monotone | 5.212 | 61.714 | 2.489 | 35.797 | 62.959 | | Paired | 17.334 | 65.628 | 0.520 | 33.852 | 65.888 | Read the flop types this way: rainbow has three suits, two-tone has two cards of one suit, monotone has three, and paired repeats a rank. ## Compared with a random hand Start from the random-hand figures, 63.29% for 66 and 57.38% for A2s. This opponent changes them by +3.26 and -23.93 points. **66 and A2s here compared with each against a random hand, in percent** | Case | Equity here | Against a random hand | Change in points | Times the random-hand equity | | --- | --- | --- | --- | --- | | 66, all flops | 66.551 | 63.285 | +3.266 | 1.05161 | | 66, rainbow, ten or higher | 66.060 | 63.285 | +2.775 | 1.04385 | | 66, rainbow, nine or lower | 81.510 | 63.285 | +18.225 | 1.28798 | | 66, two-tone | 65.638 | 63.285 | +2.353 | 1.03718 | | 66, monotone | 62.959 | 63.285 | -0.326 | 0.99485 | | 66, paired | 65.888 | 63.285 | +2.603 | 1.04113 | | A2s, all flops | 33.449 | 57.379 | -23.930 | 0.58295 | | A2s, rainbow, ten or higher | 33.940 | 57.379 | -23.439 | 0.59151 | | A2s, rainbow, nine or lower | 18.490 | 57.379 | -38.889 | 0.32224 | | A2s, two-tone | 34.362 | 57.379 | -23.017 | 0.59886 | | A2s, monotone | 37.041 | 57.379 | -20.338 | 0.64555 | | A2s, paired | 34.112 | 57.379 | -23.267 | 0.59450 | ## Does a shared suit matter? When the hands share a suit, 66 holds 66.86%; when they do not, it holds 66.24%. 66 does better with a shared suit, by 0.62 points. **66 against A2s by suit overlap, in percent** | Deals | Specific deals | Share of deals | 66 wins | Ties | A2s wins | 66 equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 12 | 50.00 | 66.597 | 0.525 | 32.878 | 66.860 | | No shared suit | 12 | 50.00 | 66.025 | 0.436 | 33.539 | 66.243 | ## How often this matchup comes up Out of 1,624,350 ways to deal two seats two cards each, 24 are 66 in one seat and A2s in the other (0.0015%); with the seats swapped too, 48 (0.0030%). ## A worked example Take a $200 pot built from $100 each. 66's equity of 66.55% is worth $133.10, a $33.10 edge, and A2s' 33.45% is worth $66.90, which is $33.10 under its stake. A thousand deals look like this: 66 takes 663, A2s takes 332, 5 are ties. ## The same matchup from the other side Swap the hands and you get A2s with 33.45% against 66 with 66.55%. We keep one page per matchup, with the better-ranked hand first. ## Keep exploring Open the calculator with 6s6h against Ad2d already entered, a deal with no shared suit, and change any card to try your own hand. The matchups after it each swap one hand for a nearby one in the ranking. - [Open 6s6h against Ad2d in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=6s6h&p2=Ad2d) - [66 combos](https://georgelipoker.com/combos/66.md) - [A2s combos](https://georgelipoker.com/combos/a2s.md) - [66 vs QTo](https://georgelipoker.com/equity/66-vs-qto.md) - [66 vs 44](https://georgelipoker.com/equity/66-vs-44.md) - [A9s vs A2s](https://georgelipoker.com/equity/a9s-vs-a2s.md) - [All hand matchups](https://georgelipoker.com/equity.md) ## How this was computed Each figure is a complete count over boards. Take the 24 specific deals, group them by suit pattern, deal all 1,712,304 boards against each, and compare the two seven-card hands. Equity counts a tie as half a win; the flop rows use every one of a board's ten flops. Source: our own exact count from the GeorgeLiPoker poker math library. No outside data is used. ## Related - [66 vs QTo: preflop equity](https://georgelipoker.com/equity/66-vs-qto.md) - [66 vs 44: preflop equity](https://georgelipoker.com/equity/66-vs-44.md) - [A9s vs A2s: preflop equity](https://georgelipoker.com/equity/a9s-vs-a2s.md)