How betting odds work: what they are and how to use them
How betting odds work: what they are and how to use them
When probability is expressed as a number between 0 and 1, the relationships between probability p and odds are as follows. When Moneyline odds are quoted as a positive number +X, it means that a wager pays X to 100. However in many situations, the possible loss (“stake” or “wager”) is paid up front and, if the gambler wins, the net win plus the stake is returned.
Moneyline bets are the simplest form of sports betting, focusing solely on picking a winner. Some bets involve combining multiple outcomes for higher rewards, while others target specific in-game events or achievements. Once you’re familiar with the basic math, fractional odds become an easy way to see potential profits relative to the stake. They’re especially popular in horse racing, where bettors often look for value in underdog picks or assess returns more precisely using this format. Fractional odds can be a bit trickier to calculate quickly, but they’re favored by many bettors for how clearly they represent the risk-reward ratio.
The use of odds in gambling facilitates betting on events where the probabilities of different outcomes vary. However, in more variable situations, such as a multi-runner horse race or a football match between two unequally matched teams, betting “at odds” provides the possibility to take the respective likelihoods of the possible outcomes into account. Similarly, fair betting odds can be expressed as “(1−p)/p to 1”, “1/p for 1”, “+100(1−p)/p”, “−100p/(1−p)”, “D−N to N”, “D for N”, “+100(D−N)/N”, or “−100N/(D−N)”. In gambling, odds are often given as the ratio of the possible net profit to the possible net loss, and sometimes this is called fractional odds.
Major sportsbooks now operate nationwide, often adjusting their lines independently or using odds from other sources, not just Las Vegas. For decades, Vegas was seen as the gold standard for odds-setting, with casinos along the Strip acting as trendsetters for the broader betting market. Sharp action – bets placed by professional or experienced bettors – also triggers line movement.
Before you rely on one, check how many bookmakers it covers, how quickly the prices are refreshed, whether it shows markets beyond the match result and whether it keeps the history of every price move. If you are new to sports betting or have been betting for years, the betting odds today shown for each match tell you where every price is best, so a winning bet always pays out as much as it can. Open our American football odds page for the next games, with past results and the prices they closed at. We cover the NHL, the SHL in Sweden and the KHL among many hockey leagues, with prices on single games and on the outright winners. Basketball goes from NBA odds and the EuroLeague to domestic leagues such as the Super Lig in Turkey and the LNB in France, with prices on single games and on the outright winners. Before a bet, check the archived results and historical odds of the teams or players involved, across leagues and tournaments worldwide.
Instead of betting on a single game, you’re predicting outcomes like who will win the NBA championship, MVP award, or a division title. Bettors predict whether the total points scored will be above or below a set number. For example, if a team is -5.5, they need to win by 6 or more points to win the bet. Instead of just picking a winner, you’re betting on whether a team can “cover the spread,” meaning they either win by a certain margin or avoid losing by too much. If you see +250, that team is the underdog; a $100 bet would return $250 if they win.
The key to understanding decimal odds is that they directly represent the total return. Decimal odds are the simplest format for many bettors, popular across Europe, Canada, and Australia. When novice bettors first realize that -125, 1.80 and 4/5 all represent the same probability, it can make them dizzy – but we’re here to lay it all out clearly. We have all the best resources for you to get started on your sports betting journey Our coverage of real money casino bonuses and highest payout casinos ensures you always get the most out of your online gaming experience. Nearly 40 states with legal sports betting signify continued growth, and we continue reporting on new launches and proposed iGaming legislation.
Covers leads the way in delivering trusted sports betting insights and analysis for 30 years and counting. Tap into our sports betting community to get the most out of your next bet. Learn from and share your tips & picks with your fellow sports bettors. The odds or amounts the bookmaker new betting sites will pay are determined by the total amount that has been bet on all of the possible events. Sports information services are often used by professional and semi-professional sports bettors to help achieve this goal.
However, not all fractional odds are traditionally read using the lowest common denominator (i.e. simplifying the fraction when possible). In either case, having won, the bettor always receives the original stake back too; so if the odds are 4/1 the bettor receives a total of £500 (£400 plus the original £100). Favoured by bookmakers in the United Kingdom and Ireland, and also common in horse racing, fractional odds quote the net profit that will be paid out to the bettor, should they win, relative to the stake. That value may be regarded as the relative probability the event will happen, expressed as a fraction (if it is less than 1), or a multiple (if it is equal to or greater than one) of the likelihood that the event will not happen. The odds are a ratio of probabilities; an odds ratio is a ratio of odds, that is, a ratio of ratios of probabilities. In probability theory and statistics, odds and similar ratios may be more natural or more convenient than probabilities.