--- title: "ATs vs A9o: preflop equity" url: "https://georgelipoker.com/equity/ats-vs-a9o.md" canonical_url: "https://georgelipoker.com/equity/ats-vs-a9o" last_updated: "2026-10-23" type: "reference" summary: "ATs is a big favorite over A9o before the flop: 73.22% to 26.78% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/ats-vs-kjo.md", "https://georgelipoker.com/equity/ats-vs-55.md", "https://georgelipoker.com/equity/aqo-vs-a9o.md"] --- # ATs vs A9o: preflop equity ATs is a big favorite over A9o before the flop: 73.22% to 26.78% equity, counted exactly over every board, with the split by flop type and suit. In equity, ATs against A9o stands at 73.22% to 26.78%, a gap of 46.44 points. ## ATs against A9o: the numbers **Exact preflop results for ATs against A9o, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | ATs | 68.159 | 10.130 | 21.711 | 73.224 | | A9o | 21.711 | 10.130 | 68.159 | 26.776 | Here a suited hand (ATs) meets an offsuit hand (A9o). Because the hands share one rank, the one with the higher kicker is ahead when that rank pairs and the other hand is mostly drawing. A lead of 46.44 points is large but not decisive: A9o still takes about 217 of every 1,000 deals. 10.13% of boards are ties, so the equity of each hand is its win rate plus half of that. ATs ranks number 13 of 169 starting hands, and A9o ranks number 25, by equity against a random hand. **Boards behind the percentages: 61,642,944 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | ATs | 42,015,000 | 6,244,000 | 13,383,000 | | A9o | 13,383,000 | 6,244,000 | 42,015,000 | The board total is exact, 36 deals at 1,712,304 boards each. Won, tied and lost counts are rounded to the nearest thousand from the five-decimal percentages. **ATs against A9o read as odds** | Hand | Equity as odds (to 1) | Wins one deal in | Loses one deal in | Pot odds needed to call (to 1) | | --- | --- | --- | --- | --- | | ATs | 2.735 | 1.467 | 4.606 | 0.366 | | A9o | 0.366 | 4.606 | 1.467 | 2.735 | 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 Break the boards down by their first three cards and ATs is strongest on rainbow flops topped by a ten or better (77.59%) and weakest on low rainbow flops (nine high or lower) (63.64%). ATs stays ahead on all five textures. **ATs against A9o by flop texture, in percent** | Flop | Share of flops | ATs wins | Ties | A9o wins | ATs equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 23.905 | 73.333 | 8.510 | 18.157 | 77.588 | | Rainbow, nine or lower | 7.042 | 61.536 | 4.206 | 34.258 | 63.639 | | Two-tone | 46.527 | 70.950 | 7.114 | 21.936 | 74.507 | | Monotone | 5.192 | 62.902 | 7.516 | 29.582 | 66.660 | | Paired | 17.334 | 57.795 | 23.649 | 18.556 | 69.620 | 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 How much does the opponent matter? Compared with its random-hand 64.60%, ATs changes by +8.62 points, and A9o, from 60.77%, by -33.99. **ATs and A9o 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 | | --- | --- | --- | --- | --- | | ATs, all flops | 73.224 | 64.602 | +8.622 | 1.13346 | | ATs, rainbow, ten or higher | 77.588 | 64.602 | +12.986 | 1.20102 | | ATs, rainbow, nine or lower | 63.639 | 64.602 | -0.963 | 0.98509 | | ATs, two-tone | 74.507 | 64.602 | +9.905 | 1.15332 | | ATs, monotone | 66.660 | 64.602 | +2.058 | 1.03186 | | ATs, paired | 69.620 | 64.602 | +5.018 | 1.07768 | | A9o, all flops | 26.776 | 60.773 | -33.997 | 0.44059 | | A9o, rainbow, ten or higher | 22.412 | 60.773 | -38.361 | 0.36878 | | A9o, rainbow, nine or lower | 36.361 | 60.773 | -24.412 | 0.59831 | | A9o, two-tone | 25.493 | 60.773 | -35.280 | 0.41948 | | A9o, monotone | 33.340 | 60.773 | -27.433 | 0.54860 | | A9o, paired | 30.380 | 60.773 | -30.393 | 0.49989 | ## Does a shared suit matter? Suit overlap shows up in the numbers. With a suit in common ATs has 72.97% equity, and with none in common it has 73.35%. ATs does better with no shared suit, by 0.38 points. **ATs against A9o by suit overlap, in percent** | Deals | Specific deals | Share of deals | ATs wins | Ties | A9o wins | ATs equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 12 | 33.33 | 67.852 | 10.240 | 21.908 | 72.972 | | No shared suit | 24 | 66.67 | 68.312 | 10.075 | 21.613 | 73.350 | ## How often this matchup comes up You will meet this exact matchup 0.0044% of the time in a random heads-up deal: 72 of 1,624,350, counting either seat order. ## A worked example Put $100 each into a $200 pot and deal every board once: ATs averages $146.44 back, ahead of its $100 by $46.44, while A9o averages $53.56, short of its $100 by $46.44. Think in thousands: about 682 of 1,000 go to ATs, about 217 go to A9o, and about 101 are chopped. ## The same matchup from the other side The reversed view, A9o against ATs, shows 26.78% for A9o and 73.22% for ATs. It is the same count, so it redirects here. ## Keep exploring AsTs against Ah9d 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 AsTs against Ah9d in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=AsTs&p2=Ah9d) - [ATs combos](https://georgelipoker.com/combos/ats.md) - [A9o combos](https://georgelipoker.com/combos/a9o.md) - [ATs vs KJo](https://georgelipoker.com/equity/ats-vs-kjo.md) - [ATs vs 55](https://georgelipoker.com/equity/ats-vs-55.md) - [AQo vs A9o](https://georgelipoker.com/equity/aqo-vs-a9o.md) - [All hand matchups](https://georgelipoker.com/equity.md) ## How this was computed The page is built from a full enumeration: 1,712,304 boards, every suit pattern of the 36 specific deals, both seven-card hands evaluated. A tie is worth half a win to each hand, and a board is tallied under each of its ten possible flops for the texture rows. Source: our own exact count from the GeorgeLiPoker poker math library. No outside data is used. ## Related - [ATs vs KJo: preflop equity](https://georgelipoker.com/equity/ats-vs-kjo.md) - [ATs vs 55: preflop equity](https://georgelipoker.com/equity/ats-vs-55.md) - [AQo vs A9o: preflop equity](https://georgelipoker.com/equity/aqo-vs-a9o.md)