--- title: "55 vs T9o: preflop equity" url: "https://georgelipoker.com/equity/55-vs-t9o.md" canonical_url: "https://georgelipoker.com/equity/55-vs-t9o" last_updated: "2026-10-23" type: "reference" summary: "55 vs T9o is close to a coin flip before the flop: 49.99% to 50.01% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/55-vs-98s.md", "https://georgelipoker.com/equity/55-vs-22.md", "https://georgelipoker.com/equity/qjs-vs-t9o.md"] --- # 55 vs T9o: preflop equity 55 vs T9o is close to a coin flip before the flop: 49.99% to 50.01% equity, counted exactly over every board, with the split by flop type and suit. Counting every board, the equity split is 50.01% for T9o and 49.99% for 55, so T9o leads by 0.02 points. ## 55 against T9o: the numbers **Exact preflop results for 55 against T9o, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | 55 | 49.523 | 0.938 | 49.539 | 49.992 | | T9o | 49.539 | 0.938 | 49.523 | 50.008 | 55 is a pocket pair and T9o is an offsuit hand. One hand holds a pair and the other holds two cards that both outrank it, which keeps the equity closer than most people expect. This is as close to a perfect coin flip as two starting hands get. Ties are part of the picture: 0.94% of boards end in a split pot, and each side counts that as half a win. Among the 169 starting hands, 55 is number 27 and T9o is number 78 by strength against a random hand. **Boards behind the percentages: 123,285,888 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | 55 | 61,055,000 | 1,156,000 | 61,075,000 | | T9o | 61,075,000 | 1,156,000 | 61,055,000 | Exact total: 72 deals times 1,712,304 boards. The other three counts come from the five-decimal percentages and are rounded to the nearest thousand, so read them as approximate. **55 against T9o read as odds** | Hand | Equity as odds (to 1) | Wins one deal in | Loses one deal in | Pot odds needed to call (to 1) | | --- | --- | --- | --- | --- | | 55 | 1.000 | 2.019 | 2.019 | 1.000 | | T9o | 1.000 | 2.019 | 2.019 | 1.000 | The final column gives the least the pot must offer for each unit called for a call to break even at this equity. ## Who is ahead on which flops The flop changes the picture. T9o does best on rainbow flops topped by a ten or better, at 52.32%, and worst on low rainbow flops (nine high or lower), at 44.19%. The lead reverses on low rainbow flops (nine high or lower) and paired flops: there 55 is the favorite even though T9o is ahead overall. **55 against T9o by flop texture, in percent** | Flop | Share of flops | 55 wins | Ties | T9o wins | 55 equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 25.341 | 47.396 | 0.561 | 52.043 | 47.677 | | Rainbow, nine or lower | 5.689 | 55.516 | 0.584 | 43.900 | 55.808 | | Two-tone | 46.485 | 48.738 | 0.551 | 50.711 | 49.014 | | Monotone | 5.151 | 46.651 | 2.071 | 51.278 | 47.686 | | Paired | 17.334 | 53.625 | 2.303 | 44.072 | 54.777 | 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 60.33%, 55 changes by -10.34 points, and T9o, from 51.53%, by -1.52. **55 and T9o 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 | | --- | --- | --- | --- | --- | | 55, all flops | 49.992 | 60.325 | -10.333 | 0.82871 | | 55, rainbow, ten or higher | 47.677 | 60.325 | -12.648 | 0.79034 | | 55, rainbow, nine or lower | 55.808 | 60.325 | -4.517 | 0.92512 | | 55, two-tone | 49.014 | 60.325 | -11.311 | 0.81250 | | 55, monotone | 47.686 | 60.325 | -12.639 | 0.79048 | | 55, paired | 54.777 | 60.325 | -5.548 | 0.90803 | | T9o, all flops | 50.008 | 51.532 | -1.524 | 0.97043 | | T9o, rainbow, ten or higher | 52.323 | 51.532 | +0.791 | 1.01535 | | T9o, rainbow, nine or lower | 44.192 | 51.532 | -7.340 | 0.85756 | | T9o, two-tone | 50.986 | 51.532 | -0.546 | 0.98940 | | T9o, monotone | 52.314 | 51.532 | +0.782 | 1.01518 | | T9o, paired | 45.223 | 51.532 | -6.309 | 0.87757 | ## Does a shared suit matter? Of the deals of this matchup, 60 share a suit (T9o at 50.10%) and 12 do not (49.54%). T9o does better with a shared suit, by 0.56 points. **55 against T9o by suit overlap, in percent** | Deals | Specific deals | Share of deals | 55 wins | Ties | T9o wins | 55 equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 60 | 83.33 | 49.423 | 0.952 | 49.625 | 49.899 | | No shared suit | 12 | 16.67 | 50.028 | 0.863 | 49.109 | 50.459 | ## How often this matchup comes up 55 against T9o is made up of 72 specific-card matchups in one seat order, 0.0044% of the 1,624,350 ordered deals, and 144 counting both seat orders, 0.0089%. ## A worked example Take a $200 pot built from $100 each. T9o's equity of 50.01% is worth $100.02, a $0.02 edge, and 55's 49.99% is worth $99.98, which is $0.02 under its stake. Over a long run, 1,000 deals split into about 496 for T9o, 495 for 55 and 9 tied. ## The same matchup from the other side T9o against 55 adds nothing new: it is 50.01% for T9o and 49.99% for 55, the same figures reversed. ## Keep exploring Try 5s5h against Td9c in the calculator: the hands share no suit, and every card can be changed. The links after it are the closest matchups in the ranking. - [Open 5s5h against Td9c in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=5s5h&p2=Td9c) - [55 combos](https://georgelipoker.com/combos/55.md) - [T9o combos](https://georgelipoker.com/combos/t9o.md) - [55 vs 98s](https://georgelipoker.com/equity/55-vs-98s.md) - [55 vs 22](https://georgelipoker.com/equity/55-vs-22.md) - [QJs vs T9o](https://georgelipoker.com/equity/qjs-vs-t9o.md) - [All hand matchups](https://georgelipoker.com/equity.md) ## How this was computed Method: exact enumeration. The 72 specific deals are grouped by suit pattern, each is run against all 1,712,304 boards, and both seven-card hands are scored. Equity adds half of every tie, and flop textures are tallied over the ten flops inside each board. Source: our own exact count from the GeorgeLiPoker poker math library. No outside data is used. ## Related - [55 vs 98s: preflop equity](https://georgelipoker.com/equity/55-vs-98s.md) - [55 vs 22: preflop equity](https://georgelipoker.com/equity/55-vs-22.md) - [QJs vs T9o: preflop equity](https://georgelipoker.com/equity/qjs-vs-t9o.md)