--- title: "JJ vs K9o: preflop equity" url: "https://georgelipoker.com/equity/jj-vs-k9o.md" canonical_url: "https://georgelipoker.com/equity/jj-vs-k9o" last_updated: "2026-10-23" type: "reference" summary: "JJ is a big favorite over K9o before the flop: 71.97% to 28.03% equity, counted exactly over every board, with the split by flop type and suit." related: ["https://georgelipoker.com/equity/jj-vs-q9s.md", "https://georgelipoker.com/equity/jj-vs-jts.md", "https://georgelipoker.com/equity/tt-vs-k9o.md"] --- # JJ vs K9o: preflop equity JJ is a big favorite over K9o before the flop: 71.97% to 28.03% equity, counted exactly over every board, with the split by flop type and suit. The exact count puts JJ at 71.97% and K9o at 28.03% when the two hands see all five board cards. ## JJ against K9o: the numbers **Exact preflop results for JJ against K9o, in percent** | Hand | Wins | Ties | Loses | Equity | | --- | --- | --- | --- | --- | | JJ | 71.780 | 0.379 | 27.841 | 71.970 | | K9o | 27.841 | 0.379 | 71.780 | 28.030 | Here a pocket pair (JJ) meets an offsuit hand (K9o). 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. A lead of 43.94 points is large but not decisive: K9o still takes about 278 of every 1,000 deals. A split pot comes up on 0.38% of boards, so the wins and the equity differ by half of that. In the ranking of all 169 starting hands, JJ is number 4 and K9o is number 40. **Boards behind the percentages: 123,285,888 counted in all** | Hand | Boards won, about | Boards tied, about | Boards lost, about | | --- | --- | --- | --- | | JJ | 88,495,000 | 467,000 | 34,324,000 | | K9o | 34,324,000 | 467,000 | 88,495,000 | 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. **JJ against K9o read as odds** | Hand | Equity as odds (to 1) | Wins one deal in | Loses one deal in | Pot odds needed to call (to 1) | | --- | --- | --- | --- | --- | | JJ | 2.568 | 1.393 | 3.592 | 0.389 | | K9o | 0.389 | 3.592 | 1.393 | 2.568 | In the last column, a pot-to-call ratio at or above the figure makes a call break even or better at this equity. ## Who is ahead on which flops If you know the kind of flop that came, the numbers shift: JJ holds 82.13% on low rainbow flops (nine high or lower) and 67.20% on monotone flops. JJ stays ahead on all five textures. **JJ against K9o by flop texture, in percent** | Flop | Share of flops | JJ wins | Ties | K9o wins | JJ equity | | --- | --- | --- | --- | --- | --- | | Rainbow, ten or higher | 23.988 | 68.839 | 0.149 | 31.012 | 68.914 | | Rainbow, nine or lower | 7.042 | 81.623 | 1.015 | 17.362 | 82.131 | | Two-tone | 46.485 | 71.218 | 0.331 | 28.451 | 71.384 | | Monotone | 5.151 | 66.341 | 1.713 | 31.946 | 67.198 | | Paired | 17.334 | 74.974 | 0.172 | 24.854 | 75.060 | 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 A random hand would give JJ 77.47% and K9o 57.81%. Against each other the change is -5.50 points for JJ and -29.78 for K9o. **JJ and K9o 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 | | --- | --- | --- | --- | --- | | JJ, all flops | 71.970 | 77.469 | -5.499 | 0.92902 | | JJ, rainbow, ten or higher | 68.914 | 77.469 | -8.555 | 0.88957 | | JJ, rainbow, nine or lower | 82.131 | 77.469 | +4.662 | 1.06018 | | JJ, two-tone | 71.384 | 77.469 | -6.085 | 0.92145 | | JJ, monotone | 67.198 | 77.469 | -10.271 | 0.86742 | | JJ, paired | 75.060 | 77.469 | -2.409 | 0.96890 | | K9o, all flops | 28.030 | 57.812 | -29.782 | 0.48485 | | K9o, rainbow, ten or higher | 31.086 | 57.812 | -26.726 | 0.53771 | | K9o, rainbow, nine or lower | 17.869 | 57.812 | -39.943 | 0.30909 | | K9o, two-tone | 28.616 | 57.812 | -29.196 | 0.49498 | | K9o, monotone | 32.802 | 57.812 | -25.010 | 0.56739 | | K9o, paired | 24.940 | 57.812 | -32.872 | 0.43140 | ## Does a shared suit matter? Two kinds of deal exist here. In 60 of them the hands share a suit and JJ holds 72.01%. In 12 they do not, and it holds 71.79%. The two rows differ by only 0.22 points, so suits barely change this matchup. **JJ against K9o by suit overlap, in percent** | Deals | Specific deals | Share of deals | JJ wins | Ties | K9o wins | JJ equity | | --- | --- | --- | --- | --- | --- | --- | | Share a suit | 60 | 83.33 | 71.809 | 0.395 | 27.796 | 72.006 | | No shared suit | 12 | 16.67 | 71.636 | 0.300 | 28.064 | 71.786 | ## How often this matchup comes up Exactly 72 specific deals fit this matchup in one seat order, which is 0.0044% of 1,624,350; both orders together give 144, or 0.0089%. ## A worked example Worked example: both players commit $100, so $200 sits in the middle. Over every board, JJ's average share is $143.94 (a gain of $43.94) and K9o's is $56.06 (a loss of $43.94). Out of 1,000 deals you should see around 718 outright wins for JJ, 278 for K9o, and 4 split pots. ## The same matchup from the other side K9o against JJ adds nothing new: it is 28.03% for K9o and 71.97% for JJ, the same figures reversed. ## Keep exploring Try JsJh against Kd9c 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 JsJh against Kd9c in the equity calculator](https://georgelipoker.com/tools/equity-calculator.md#p1=JsJh&p2=Kd9c) - [JJ combos](https://georgelipoker.com/combos/jj.md) - [K9o combos](https://georgelipoker.com/combos/k9o.md) - [JJ vs Q9s](https://georgelipoker.com/equity/jj-vs-q9s.md) - [JJ vs JTs](https://georgelipoker.com/equity/jj-vs-jts.md) - [TT vs K9o](https://georgelipoker.com/equity/tt-vs-k9o.md) - [All hand matchups](https://georgelipoker.com/equity.md) ## How this was computed All 1,712,304 five-card boards are dealt for every suit pattern among the 72 specific deals of JJ against K9o, and both hands are scored on each. That is a full count, so the percentages are exact. Ties are half a win each, and each board appears once per flop it contains. Source: our own exact count from the GeorgeLiPoker poker math library. No outside data is used. ## Related - [JJ vs Q9s: preflop equity](https://georgelipoker.com/equity/jj-vs-q9s.md) - [JJ vs JTs: preflop equity](https://georgelipoker.com/equity/jj-vs-jts.md) - [TT vs K9o: preflop equity](https://georgelipoker.com/equity/tt-vs-k9o.md)