--- title: "A9s vs A4s: preflop equity" url: "https://georgelipoker.com/equity/a9s-vs-a4s.md" canonical_url: "https://georgelipoker.com/equity/a9s-vs-a4s" last_updated: "2026-10-23" type: "reference" summary: "A9s is a big favorite over A4s before the flop: 65.53% to 34.47% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/a9s-vs-a3s.md", "https://georgelipoker.com/equity/a9s-vs-qjo.md", "https://georgelipoker.com/equity/ato-vs-a4s.md"] --- # A9s vs A4s: preflop equity A9s is a big favorite over A4s before the flop: 65.53% to 34.47% equity, counted exactly over every board, with the split by flop type and suit. Averaged over every possible board, A9s is ahead of A4s by 31.06 points of equity, 65.53% to 34.47%. ## A9s against A4s: the numbers **Exact preflop results for A9s against A4s, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | A9s | 58.445 | 14.169 | 27.386 | 65.530 | | A4s | 27.386 | 14.169 | 58.445 | 34.470 | Here suited hands face each other, A9s on one side and A4s on the other. The two hands share a rank, and the one with the better other card dominates: it wins most kicker battles when that shared rank hits. A lead of 31.06 points is large but not decisive: A4s still takes about 274 of every 1,000 deals. Ties are 14.17% of the outcomes here; each tied board gives both hands half the pot. Place 18 of 169 belongs to A9s and place 35 belongs to A4s in the ranking against a random hand. **Boards behind the percentages: 20,547,648 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | A9s | 12,009,000 | 2,911,000 | 5,627,000 | | A4s | 5,627,000 | 2,911,000 | 12,009,000 | The board total is exact, 12 deals at 1,712,304 boards each. Won, tied and lost counts are rounded to the nearest thousand from the five-decimal percentages. **A9s against A4s read as odds** | Hand | Equity as odds (to 1) | Wins one deal in | Loses one deal in | Pot odds needed to call (to 1) | | --- | --- | --- | --- | --- | | A9s | 1.901 | 1.711 | 3.652 | 0.526 | | A4s | 0.526 | 3.652 | 1.711 | 1.901 | The last column is the break-even price: the pot odds a call needs to offer, as a ratio of pot to call. ## Who is ahead on which flops A9s prefers rainbow flops topped by a ten or better, where it holds 68.84%, and likes monotone flops least, where it holds 61.23%. A9s stays ahead on all five textures. **A9s against A4s by flop texture, in percent** | Flop | Share of flops | A9s wins | Ties | A4s wins | A9s equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 24.526 | 61.946 | 13.780 | 24.274 | 68.836 | | Rainbow, nine or lower | 6.383 | 62.970 | 3.350 | 33.680 | 64.645 | | Two-tone | 46.543 | 60.433 | 10.430 | 29.137 | 65.648 | | Monotone | 5.215 | 55.993 | 10.470 | 33.537 | 61.228 | | Paired | 17.333 | 47.226 | 29.858 | 22.916 | 62.155 | 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, 62.78% for A9s and 59.03% for A4s. This opponent changes them by +2.75 and -24.56 points. **A9s and A4s 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 | | --- | --- | --- | --- | --- | | A9s, all flops | 65.530 | 62.781 | +2.749 | 1.04379 | | A9s, rainbow, ten or higher | 68.836 | 62.781 | +6.055 | 1.09645 | | A9s, rainbow, nine or lower | 64.645 | 62.781 | +1.864 | 1.02969 | | A9s, two-tone | 65.648 | 62.781 | +2.867 | 1.04567 | | A9s, monotone | 61.228 | 62.781 | -1.553 | 0.97526 | | A9s, paired | 62.155 | 62.781 | -0.626 | 0.99003 | | A4s, all flops | 34.470 | 59.034 | -24.564 | 0.58390 | | A4s, rainbow, ten or higher | 31.164 | 59.034 | -27.870 | 0.52790 | | A4s, rainbow, nine or lower | 35.355 | 59.034 | -23.679 | 0.59889 | | A4s, two-tone | 34.352 | 59.034 | -24.682 | 0.58190 | | A4s, monotone | 38.772 | 59.034 | -20.262 | 0.65677 | | A4s, paired | 37.845 | 59.034 | -21.189 | 0.64107 | ## Does a shared suit matter? For this pair the shared-suit row is empty: the two hands cannot both own a card of one suit without reusing a card. **A9s against A4s by suit overlap, in percent** | Deals | Specific deals | Share of deals | A9s wins | Ties | A4s wins | A9s equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 0 | 0.00 | not possible | not possible | not possible | not possible | | No shared suit | 12 | 100.00 | 58.445 | 14.169 | 27.386 | 65.530 | ## How often this matchup comes up Out of 1,624,350 ways to deal two seats two cards each, 12 are A9s in one seat and A4s in the other (0.0007%); with the seats swapped too, 24 (0.0015%). ## A worked example Put $100 each into a $200 pot and deal every board once: A9s averages $131.06 back, ahead of its $100 by $31.06, while A4s averages $68.94, short of its $100 by $31.06. Scaled to 1,000 deals, that is roughly 584 wins for A9s, 274 for A4s and 142 chopped pots. ## The same matchup from the other side If you came looking for A4s against A9s, the numbers are the same with the hands swapped: 34.47% and 65.53%. ## Keep exploring As9s against Ah4h is a ready-made deal for the calculator, with no suit in common between the hands. The neighboring matchups below replace one hand with another of similar strength. - [Open As9s against Ah4h in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=As9s&p2=Ah4h) - [A9s combos](https://georgelipoker.com/combos/a9s.md) - [A4s combos](https://georgelipoker.com/combos/a4s.md) - [A9s vs A3s](https://georgelipoker.com/equity/a9s-vs-a3s.md) - [A9s vs QJo](https://georgelipoker.com/equity/a9s-vs-qjo.md) - [ATo vs A4s](https://georgelipoker.com/equity/ato-vs-a4s.md) - [All hand matchups](https://georgelipoker.com/equity.md) ## How this was computed Nothing here is simulated. The 12 deals of A9s against A4s fall into a few suit patterns, each dealt against all 1,712,304 boards, with both best five-card hands compared on every board. Ties give each hand half a win, and the flop rows count a board under each of its ten flops. Source: our own exact count from the GeorgeLiPoker poker math library. No outside data is used. ## Related - [A9s vs A3s: preflop equity](https://georgelipoker.com/equity/a9s-vs-a3s.md) - [A9s vs QJo: preflop equity](https://georgelipoker.com/equity/a9s-vs-qjo.md) - [ATo vs A4s: preflop equity](https://georgelipoker.com/equity/ato-vs-a4s.md)