Poker 3-Bet Chart
How often does a preflop 3-bet need to work as a pure bluff? This poker 3-bet chart lists folds needed and the opener's MDF for common sizes — 2.5× through 5× an open — in a live $1/$2 spot. Pair it with the fold equity chart, the MDF chart, the c-bet chart, and the free bluff calculator.
3-bet sizing chart: folds needed and MDF
Setup used for every row: $1/$2, open to $6, pot facing the 3-bettor = $9 (blinds $3 + open $6). You have not put chips in yet (in-position 3-bet).
| 3-bet size | % of pot | Folds a pure 3-bet needs | Opener MDF |
|---|---|---|---|
| 2.5× open ($15) | 166.7% | 62.5% | 37.5% |
| 3× open ($18) | 200% | 66.7% | 33.3% |
| 3.5× open ($21) | 233.3% | 70% | 30% |
| 4× open ($24) | 266.7% | 72.7% | 27.3% |
| 5× open ($30) | 333.3% | 76.9% | 23.1% |
Folds needed = bet ÷ (pot + bet). MDF = pot ÷ (pot + bet). They always add to 100%. Numbers assume a pure bluff (zero equity when called) heads-up versus the opener only.
The formula
Folds needed = bet ÷ (pot + bet)
MDF = pot ÷ (pot + bet) = 1 − folds needed
Same math as every other bet on this site — the shock is the size. A half-pot postflop stab needs about one fold in three. A 3× open into a $9 pot puts $18 at risk to win $9, so you need two folds in three as a pure bluff. Preflop re-raises are often 150–300% of the pot already there, which is why light 3-bets fail against sticky openers.
Compare: the overbet chart covers 100–300% pot postflop; a standard 3-bet lands in that same fold-% band before the flop even comes.
Worked example: $18 (3×) into a $9 pot
$1/$2. Villain opens to $6. Pot is $9. You make it $18.
- Folds needed (pure): 18 ÷ 27 = 66.7%. Two folds in three and the bluff breaks even.
- Opener MDF: 9 ÷ 27 = 33.3%. He must continue about one-third of the time or pure 3-bet bluffs print.
- Check: 66.7% + 33.3% = 100%.
Against a loose opener who folds 70% to 3-bets, a light $18 re-raise clears. Against a reg who continues 50%, you need equity when called — suited connectors, broadway blockers — or you should tighten the light portion. The calculator models postflop bets; use this page for the preflop size decision, then the c-bet chart once the flop lands.
Worked example: $15 (2.5×) — the cheaper light size
Same $9 pot, now a smaller 3-bet of $15 (2.5× the $6 open).
- Folds needed: 15 ÷ 24 = 62.5%.
- Opener MDF: 37.5%.
Dropping from 3× to 2.5× cuts the pure fold target from 66.7% to 62.5% and risks $3 less when called. That is why many in-position light 3-bets favor the smaller end — you still apply pressure, but the break-even bar is a little lower. Out of position, players often size up (3.5–4×) so the pot is not too small for a tougher postflop seat; that raises the bluff fold target again.
When to 3-bet small vs large
Smaller (≈2.5–3×). In position, versus opens that fold often enough, or when you want a lower break-even for light hands. You lose less when called and still deny limpers/opens a cheap flop.
Larger (≈3.5–5×). Out of position, versus smaller opens, or with hands that want a big pot (premiums). Bigger sizes force more folds from dominated hands — but as pure bluffs they need 70%+ folds in this $1/$2 setup, so keep the light share honest.
Skip the light 3-bet. Multiway pots (everyone must fold), openers who almost never fold, or no plan for the flop. Cold-calling multiway changes the math entirely. Stack depth matters too: see the SPR chart for how deep you are after the 3-bet lands.
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See it on Amazon →3-bet FAQ
What is a 3-bet in poker?
A 3-bet is a re-raise after an open raise. The blinds are the first bet, the open is the second bet, and your re-raise is the third. Live cash often 3-bets to about 3× the open in position and a touch larger out of position.
How often does a pure 3-bet bluff need to work?
Folds needed = amount you put in ÷ (pot facing you + amount you put in). Facing a $6 open into a $9 pot, a $18 3-bet (3×) needs 66.7% folds as a pure bluff; $15 (2.5×) needs 62.5%; $24 (4×) needs 72.7%. That is why light 3-bets need a clear fold target or equity when called.
Why do 3-bets need so many folds?
A 3-bet is usually a large fraction of the pot already sitting there — often ~1.5× to 3× pot — so bet ÷ (pot + bet) lands in the 60–75% range. Postflop half-pot bets only need ~33% folds; preflop re-raises are a different size class.
What is MDF facing a 3-bet?
Minimum defense frequency = pot ÷ (pot + bet). Facing a $18 3-bet into $9, MDF is 33.3%. Facing $15, MDF is 37.5%. Fold more often than that and pure 3-bet bluffs print. In practice opener ranges and stack depth change how often they should continue.
When should you 3-bet small vs large?
Smaller (≈2.5–3×) keeps the fold target lower and loses less when called — common in position. Larger (≈3.5–5×) pressures more of the open range and builds a bigger pot with strong hands, but needs more folds as a bluff and risks more chips. Out of position and versus opens that rarely fold, lean value-heavy or skip light 3-bets.