The concept of expected value (EV) describes the average outcome of a given situation at the poker table. It's not about winning a hand or two, it's about profiting in the long run. 

EV refers to the average amount of money a poker player is expected to win or lose on a particular decision over the long term. It is a mathematical concept that takes into account the probability of various outcomes and the potential payoff or loss associated with each outcome.

In order to calculate the EV, you will need to multiply the probability of each possible outcome by the potential payoff or loss associated with that outcome. Then, sum up the results. For example, you are hoping to win a $200 pot by calling a $50 bet on the river with a straight draw. You estimate that you have a 30% chance of making your straight and winning the $200 pot and a 70% chance of missing your draw and losing the $50. 

EV = probability of making your straight (0.3) x potential payoff ($200) +  probability of missing your draw (0.7) x potential loss (-$50). The expected value of the call is $25.

This means that by making this decision, you can expect to win $25, on average, in the long run. 

Knowing how to calculate expected value is fundamental in poker strategy, as it allows players to make decisions based on math and logic rather than emotion or intuition. Professional poker players maximize their profits over the long term by consistently making decisions with positive expected value. 

In Range Converter Online Viewer you can quickly see EV values for every preflop and postflop action with any combo.