Preflop All-In Odds: Matchup Math

Preflop all-in odds come down to a few repeating matchups, and knowing them turns “should I call this shove?” into a quick equity check. A pocket pair versus two overcards — the classic coin flip — is only about 55/45. A dominated hand like AQ against AK is a crushing 26% underdog. And the famous aces-over-kings cooler runs about 82/18. Learn the handful of shapes below and you’ll know your equity before the chips land.

The matchup equity table

These are the standard preflop equities (heads-up, all five community cards to come), rounded to what you’ll actually use:

Matchup	Example	Favorite equity	Underdog equity
Pair vs lower pair	AA vs KK	~82%	~18%
Pair vs two overcards (the flip)	88 vs AKo	~55%	~45%
Pair vs one over, one under	99 vs A8o	~71%	~29%
Pair vs two lower cards	QQ vs JTo	~85%	~15%
Dominated same high card	AK vs AQ	~74%	~26%
Two overcards vs two under	AKo vs 72o	~67%	~33%
Pair vs its own overcard combo	AA vs AKo	~88%	~12%

Why the coin flip is ~55/45

Take 88 vs AKo. The pair is already made; the AK must improve. AK’s main path is to pair the ace or the king — 6 outs (3 aces + 3 kings) across five community cards. Pairing one over card by the river happens a bit under half the time, and AK adds small extra equity from running straights, giving it about 43-45%.

The eights stay ahead whenever AK bricks, so they win ~55-57%. It’s called a flip because it’s nearly even — but the pair is always the slight favorite. This is equity in its rawest form: a made hand racing against live overcards.

Why domination is so brutal

Now AK vs AQ. They share an ace, which is the killer. The AQ can’t win just by pairing its ace — that pairs the king’s hand too and the king kicker plays. Effectively AQ must pair its queen (3 outs) or catch a lucky two-pair or straight, so it’s stuck around 26%, roughly 3 to 1 against.

Compare that to AK vs QJ (two live cards, no shared rank): the underdog there sits closer to 40%, because all four of its cards can pair to win. Sharing a card via blockers is what crushes the dominated hand’s outs.

Worked example: pricing a shove

You hold A♣ K♣ on the button. A tight player shoves for $100 into a pot that already has $30 (blinds + antes). You must call $100 to win $130 + your own $100 back — effectively risking $100 to win $130.

Your pot odds: $100 ÷ ($130 + $100) = $100 ÷ $230 = 43.5% needed to break even.

Now estimate equity by matchup. A tight player’s shoving range is mostly big pairs and AK:

• vs QQ+ (pairs above your cards): you’re the ~45% underdog (flip, but you’re the overcards) — just under the price.
• vs a smaller pair like TT: ~48% — essentially a flip, right at the price.
• vs AQ or worse: you dominate at ~74% — a massive call.

Because AK is suited (add a couple points) and their range includes hands you crush, your blended equity clears the 43.5% you need. Call. Without the matchup table you’d be guessing; with it, the decision is arithmetic. Put it to work most in Texas Hold’em, where these all-ins come up constantly.

Quick rules to remember

• Pair vs overcards ≈ 55/45 — the flip; the pair is always slightly ahead.
• Pair vs pair ≈ 80/20 — about 4 to 1; the lower pair needs a set.
• Dominated (shared high card) ≈ 26% — roughly 3 to 1 against; kicker must pair.
• Two live cards vs two ≈ 60/40 — closer than domination because all four cards are live.
• Suited adds ~2-4 points — factor in flush equity for the underdog.

The takeaway

Preflop all-in odds are just a small set of memorized matchups: the ~55/45 flip, the ~82/18 pair-over-pair cooler, the ~26% dominated dog, and the ~60/40 live-card race. Combine any of them with your pot odds and the call-or-fold decision answers itself. Build out the rest of the numbers in the poker odds and math hub.