AK vs AJ: what are the odds?

Ace-jack looks premium and plays like a trap. Against the hands that put real money in preflop, it is either flipping at best or dominated like this, three outs and a prayer. The jack does pull one small lever that ace-queen cannot: it opens a few extra straight runouts, which is why the number dips a point below the ace-queen matchup. That is not a consolation worth having. The practical rule for ace-jack is simple: it is a fine hand to open and a bad hand to go to war with, because wars mean ranges full of exactly the hands that dominate it.

Quick tip: If the pot gets huge preflop and you hold ace-jack, someone usually has you out-kicked or paired. Fold earlier than feels polite.

All numbers are all-in preflop equity vs one opponent, computed by the Poker Shark equity engine from the full 169 by 169 hand matrix, weighted across suited and offsuit combos.