A positive expected value (+EV) bet is one that makes money on average because the odds are bigger than the true probability of the outcome. It can still lose on any given occasion.

How do I calculate expected value?

EV = (chance of winning × profit if it wins) − (chance of losing × stake). If the result is positive, the bet is +EV; if negative, it's -EV.

Is expected value the same as value betting?

They're two sides of the same coin. Value betting is the practice of finding +EV bets — odds bigger than the true chance of the outcome.

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Betting Strategy

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Expected Value (EV) in Betting Explained

Expected value is the maths behind every profitable bet. Here's what +EV means, how to work it out, and why it matters more than any single result.

Expected value — EV — is the single most important concept in profitable betting. It's what 'value' actually means underneath the jargon, and understanding it helps you tell a tipster with a real method from one who's simply guessing.

What expected value means

Expected value is the average result you'd get if you could place the same bet thousands of times. A positive-EV (+EV) bet makes money on average; a negative-EV (-EV) bet loses money on average — even if any single bet can win or lose.

It captures the whole point of value betting: you're not trying to be right every time, you're trying to bet at odds bigger than the true chance so the maths works in your favour over the long run.

How to calculate EV

The formula is: EV = (probability of winning × profit if you win) − (probability of losing × stake).

Example: you back a selection at odds of 3.00 (a £10 stake returns £20 profit) and you believe its true chance is 40%. EV = (0.40 × £20) − (0.60 × £10) = £8 − £6 = +£2. On average this bet makes £2 every time you place it — a clear +EV bet.

Why EV beats judging bets by results

A +EV bet can lose and a -EV bet can win — over a small sample, luck dominates. That's why you should never judge a tipster on one week, or even one month.

The whole skill is repeatedly finding +EV bets and staking sensibly so that, over a large sample, the edge shows up as profit. Pair EV thinking with sound flat or proportional staking to protect your bank through the variance.