Minimum defence frequency calculator
Enter the pot and the bet you face. See how many of your hands to keep playing so that a bluff does not pay, how often a bluff must work, and what your call needs.
On the river, a bettor who mixes bluffs in at this size has one bluff for every 3 strong hands.
How the figure is worked out
Minimum defence frequency is the share of your hands you must keep playing, by calling or raising, so that the opponent cannot bet with any two cards and make money. It is the pot divided by the pot plus the bet. Facing a $50 bet into $100, it is 100 divided by 150: two hands in three.
Fold more than that and a bluff with nothing shows a profit, which is the gap a thinking player looks for. The other two figures come from the same sum: a bluff needs the bet divided by the pot plus the bet in folds, and a call needs the bet divided by the whole pot after your call.
It is a guide, not a rule. Many players at small stakes bluff less often than their bet size allows, and against them folding more than this is fine. Against a player who bets at almost every pot, keeping to it stops his bluffs from paying.
The common bet sizes
| Bet size | Keep playing with | A bluff needs folds | A call needs to win |
|---|---|---|---|
| A quarter of the pot | 80.0% | 20.0% | 16.7% |
| A third of the pot | 75.0% | 25.0% | 20.0% |
| Half the pot | 66.7% | 33.3% | 25.0% |
| Two thirds of the pot | 60.0% | 40.0% | 28.6% |
| Three quarters of the pot | 57.1% | 42.9% | 30.0% |
| The pot | 50.0% | 50.0% | 33.3% |
| Twice the pot | 33.3% | 66.7% | 40.0% |
Questions
How do I work out minimum defence frequency?
Divide the pot by the pot plus the bet. Facing a $50 bet into $100, it is 100 divided by 150, so you keep playing with two hands in three.
Is it the same as pot odds?
No. Pot odds tell you how often one call must win. Minimum defence tells you how much of all your hands must keep playing so that bluffs do not pay. Facing a pot-size bet, a call needs to win 33.3% of the time, and you keep playing with half of your hands.
Should I always defend that often?
No. It protects you against a player who bluffs as often as his bet size allows. Many players at small stakes bluff less than that, and against them folding more is fine.