Calculate the price you are being offered
Divide the call amount by the final pot after you call. If the pot is €40 and your opponent bets €20, you face a €20 call into a pot that currently contains €60. After calling, the total would be €80: 20 ÷ 80 = 25%.
That means you need about 25% equity for a break-even call when no further betting remains and other costs are ignored. Do not divide by €60: that would leave your own call out of the final pot.
Count useful outs, not just attractive cards
An out is a card that can improve your hand enough to win. A flush draw often has nine potential outs, but some may also improve an opponent to a better hand. Your estimate depends on the range you give that opponent.
Be careful about which cards you will actually get to see. Facing a turn bet, only the river remains. Facing a flop bet does not necessarily buy both remaining cards: your opponent may bet again on the turn.
Immediate odds and implied odds
Immediate pot odds use the money already available. Implied odds consider additional money you might win after improving. That extra payment is an estimate, not a promise.
Stack depth, position and how obvious your draw will be all matter. Also consider the reverse case: you improve and still pay off a stronger hand. A generous-looking future payout should not excuse every call.
A positive EV decision can still lose
Imagine an all-in call costing €20 for a final pot of €80, with 30% equity. You win €60 net when you win and lose €20 when you lose. Its EV is 0.30 × €60 - 0.70 × €20 = +€4, ignoring fees and split pots.
You will still lose that example more often than you win it. The positive average comes from the size of the wins relative to the losses. Review the quality of the equity estimate and the calculation rather than treating one result as the verdict.
