Betting guides: value bets, EV, margin and Kelly
Four short guides to betting maths: how to find a value bet, how to calculate expected value (EV), how bookmaker margin works, and how much of your bankroll to stake with the Kelly criterion. Each one gives a plain explanation, the calculation formula and a worked example with real numbers, no jargon. Written for anyone who wants to understand why one price is better than another, not just spot a big number.
- What is a value bet and how to find oneA value bet is a bet whose odds are higher than the fair odds implied by the outcome's true probability. Explained with a worked example.
- Expected value (EV) in betting: formula and examplesHow to calculate the expected value (EV) of a bet: the formula, worked examples with odds, and why it only shows over many bets.
- Bookmaker margin: what it is and how to calculate itWhat bookmaker margin is, how to calculate it from the odds and how to remove it to get fair probabilities. With worked examples.
- Kelly criterion: how much of your bankroll to stakeThe Kelly criterion tells you what share of your bankroll to stake when a bet has positive expected value. Formula, example and why to use fractional Kelly.
Put it into practice
kefas continuously collects odds from Lithuanian bookmakers and shows the highest price on offer for every pick.
Betting always carries risk: even a positive-EV bet can lose. Only stake what you can afford to lose, and if gambling is becoming a problem, seek help.