--- title: "99 vs A4s: preflop equity" url: "https://georgelipoker.com/equity/99-vs-a4s.md" canonical_url: "https://georgelipoker.com/equity/99-vs-a4s" last_updated: "2026-10-23" type: "reference" summary: "99 is a big favorite over A4s before the flop: 66.56% to 33.44% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/99-vs-a3s.md", "https://georgelipoker.com/equity/99-vs-qjo.md", "https://georgelipoker.com/equity/88-vs-a4s.md"] --- # 99 vs A4s: preflop equity 99 is a big favorite over A4s before the flop: 66.56% to 33.44% equity, counted exactly over every board, with the split by flop type and suit. Before any board card is dealt, 99 holds 66.56% equity against A4s, which leaves A4s with 33.44%. ## 99 against A4s: the numbers **Exact preflop results for 99 against A4s, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | 99 | 66.345 | 0.427 | 33.228 | 66.558 | | A4s | 33.228 | 0.427 | 66.345 | 33.442 | 99, a pocket pair, plays A4s, a suited hand. The pair sits between the other hand's two cards: one is higher and one is lower, so the pair is exposed to the higher card. 99 is the clear favorite, though A4s gets there on roughly one board in 3. 0.43% of boards are ties, so the equity of each hand is its win rate plus half of that. In the ranking of all 169 starting hands, 99 is number 6 and A4s is number 35. **Boards behind the percentages: 41,095,296 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | 99 | 27,265,000 | 175,000 | 13,655,000 | | A4s | 13,655,000 | 175,000 | 27,265,000 | The board total is exact, 24 deals at 1,712,304 boards each. Won, tied and lost counts are rounded to the nearest thousand from the five-decimal percentages. **99 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) | | --- | --- | --- | --- | --- | | 99 | 1.990 | 1.507 | 3.010 | 0.502 | | A4s | 0.502 | 3.010 | 1.507 | 1.990 | 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 Break the boards down by their first three cards and 99 is strongest on low rainbow flops (nine high or lower) (76.93%) and weakest on monotone flops (62.58%). 99 stays ahead on all five textures. **99 against A4s by flop texture, in percent** | Flop | Share of flops | 99 wins | Ties | A4s wins | 99 equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 25.220 | 66.049 | 0.199 | 33.752 | 66.149 | | Rainbow, nine or lower | 5.689 | 76.458 | 0.947 | 22.595 | 76.931 | | Two-tone | 46.545 | 64.808 | 0.312 | 34.880 | 64.964 | | Monotone | 5.212 | 61.381 | 2.406 | 36.213 | 62.584 | | Paired | 17.334 | 69.076 | 0.301 | 30.623 | 69.226 | Rainbow flops have three suits, two-tone flops repeat one suit, monotone flops are all one suit, and paired flops repeat a rank. ## Compared with a random hand Compared with a random opponent, this matchup shifts 99 from 72.06% by -5.50 points and A4s from 59.03% by -25.59 points. **99 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 | | --- | --- | --- | --- | --- | | 99, all flops | 66.558 | 72.057 | -5.499 | 0.92369 | | 99, rainbow, ten or higher | 66.149 | 72.057 | -5.908 | 0.91801 | | 99, rainbow, nine or lower | 76.931 | 72.057 | +4.874 | 1.06764 | | 99, two-tone | 64.964 | 72.057 | -7.093 | 0.90156 | | 99, monotone | 62.584 | 72.057 | -9.473 | 0.86853 | | 99, paired | 69.226 | 72.057 | -2.831 | 0.96071 | | A4s, all flops | 33.442 | 59.034 | -25.592 | 0.56649 | | A4s, rainbow, ten or higher | 33.851 | 59.034 | -25.183 | 0.57342 | | A4s, rainbow, nine or lower | 23.069 | 59.034 | -35.965 | 0.39077 | | A4s, two-tone | 35.036 | 59.034 | -23.998 | 0.59349 | | A4s, monotone | 37.416 | 59.034 | -21.618 | 0.63380 | | A4s, paired | 30.774 | 59.034 | -28.260 | 0.52129 | ## Does a shared suit matter? When the hands share a suit, 99 holds 66.85%; when they do not, it holds 66.26%. 99 does better with a shared suit, by 0.59 points. **99 against A4s by suit overlap, in percent** | Deals | Specific deals | Share of deals | 99 wins | Ties | A4s wins | 99 equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 12 | 50.00 | 66.618 | 0.472 | 32.910 | 66.854 | | No shared suit | 12 | 50.00 | 66.071 | 0.382 | 33.547 | 66.262 | ## How often this matchup comes up The class pair covers 24 combinations of specific cards in a fixed seat order, 0.0015% of 1,624,350, and 48 (0.0030%) in either order. ## A worked example Put $100 each into a $200 pot and deal every board once: 99 averages $133.12 back, ahead of its $100 by $33.12, while A4s averages $66.88, short of its $100 by $33.12. Scaled to 1,000 deals, that is roughly 664 wins for 99, 332 for A4s and 4 chopped pots. ## The same matchup from the other side A4s versus 99 is this same page seen from the other hand: 33.44% for A4s, 66.56% for 99. ## Keep exploring 9s9h against Ad4d 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 9s9h against Ad4d in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=9s9h&p2=Ad4d) - [99 combos](https://georgelipoker.com/combos/99.md) - [A4s combos](https://georgelipoker.com/combos/a4s.md) - [99 vs A3s](https://georgelipoker.com/equity/99-vs-a3s.md) - [99 vs QJo](https://georgelipoker.com/equity/99-vs-qjo.md) - [88 vs A4s](https://georgelipoker.com/equity/88-vs-a4s.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 - [99 vs A3s: preflop equity](https://georgelipoker.com/equity/99-vs-a3s.md) - [99 vs QJo: preflop equity](https://georgelipoker.com/equity/99-vs-qjo.md) - [88 vs A4s: preflop equity](https://georgelipoker.com/equity/88-vs-a4s.md)