// poker odds · before the flop

Odds someone has a bigger pair

I have kings: how likely is it someone has aces? The short answer is below, and under it the working: the formula with the numbers put in, and the count from dealing every possible card.

KK, 8 opponents: someone has AA3.91%exact, rounded
as a frequency1 in 25.6on average
odds against24.6 to 1misses to hits
holding AK instead1.96%3 aces left, not 4

The working

With your two cards out, 50 remain and all four aces are among them. One named opponent is dealt aces with probability C(4, 2) / C(50, 2) = 6 / 1,225. Two named opponents can both have aces only one way (the remaining two), so add the eight players and subtract the overlap (inclusion–exclusion):

P(one named player has AA)        = 6 / 1,225          = 0.490%
P(two named players both have AA) = 6 / (1,225 × 1,128) = 0.0004%
P(someone of 8 has AA) = 8 × 0.490% − 28 × 0.0004% = 3.906%

For a smaller pair the same sum runs over every higher rank. Each rank of four cards can give one opponent a pair (6 ways) or two opponents a pair each (3 ways), and the build multiplies those out exactly. A seeded simulation of 400,000 full deals per row checks the 8-opponent column; it agrees within sampling error for every pair (for kings it found 3.91%).

Every pair, every table size

Chance that at least one opponent was dealt a higher pocket pair. Columns are the number of opponents: 1 is heads-up, 5 is a 6-max table, 8 is 9-handed.

Chance an opponent holds a bigger pair
Your pair123456789
KK0.5%1.0%1.5%2.0%2.4%2.9%3.4%3.9%4.4%
QQ1.0%2.0%2.9%3.9%4.8%5.8%6.7%7.7%8.6%
JJ1.5%2.9%4.4%5.8%7.2%8.6%9.9%11.3%12.6%
TT2.0%3.9%5.8%7.6%9.5%11.3%13.0%14.8%16.5%
992.4%4.8%7.2%9.5%11.7%13.9%16.0%18.1%20.2%
882.9%5.8%8.6%11.3%13.9%16.5%18.9%21.4%23.7%
773.4%6.7%10.0%13.1%16.1%19.0%21.8%24.5%27.1%
663.9%7.7%11.3%14.8%18.2%21.4%24.5%27.5%30.3%
554.4%8.6%12.7%16.5%20.2%23.7%27.1%30.3%33.4%
444.9%9.6%14.0%18.2%22.2%26.0%29.7%33.1%36.4%
335.4%10.5%15.3%19.9%24.2%28.3%32.1%35.8%39.2%
225.9%11.4%16.6%21.5%26.1%30.4%34.5%38.3%41.9%
AK (aces only)0.2%0.5%0.7%1.0%1.2%1.5%1.7%2.0%2.2%

Queens run into a bigger pair 7.7% of the time 9-handed and jacks 11.3%; deuces, with every pair above them, 38.3%. At 6-max (5 opponents) kings meet aces 2.4% of the time.

What this does not tell you

These are the odds before anyone acts. Betting is information: if a tight player four-bets, the chance they hold aces is far higher than 3.9%, and the table cannot see that. The deal-time figure is still the right starting point, and it is why folding kings preflop at a full table is almost never right. For the price of getting it in against aces anyway, see AA vs KK.

More before the flop

Other odds

// how these numbers were computed
  • Counted, not quoted. tools/build-odds.mjs deals every possible flop, turn, river or starting hand and counts. Where a closed-form formula exists, the build refuses to publish unless the count matches it exactly.
  • Made hands come from the engine. Whether cards make a straight, a flush or a full house is decided by the same Rust/WebAssembly evaluator the trainer runs, not by hand-written rules.
  • Odds are not equity. Hitting your hand is not winning the pot. For that, the matchup pages deal every board against a specific hand and the spot calculator works against a range.
  • Raw data: odds.json.