How betting odds work: what they are and how to use them

We’ve followed social sportsbooks and sweepstakes casinos since they first started launching, and remain ahead of the game with rating the best prediction market apps. From Missouri sports betting to emerging markets, we provide actionable intel on where and how you can bet securely and legally. Making a profit in gambling involves predicting the relationship of the true probabilities to the payout odds.

A “wholesale odds” index is an index of all the prices in a probabilistic market operating at 100% competitiveness and displayed without any profit margin factored for market participants. However, if the teams are evenly matched, both teams can have a negative line at the same time (e.g. −110 −110 or −105 −115), due to house take. 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.

Enter how much you want to wager in total to see the stake for each outcome and the resulting profit. Our sure bets page shows a way to cover every outcome of a match across different bookmakers so that the combined odds return a profit, as long as the prices are still available when you place the bets. Our real-time data updates live scores as soon as a goal is scored, a point is won or a basket is made, and with live odds available for matches in-play, you can compare prices during a match and before it. You can check the opening odds of each bookmaker, follow the odds movement over time and compare it with the current odds, so you know how the market has reacted before you decide when to bet. Odds change constantly between the moment a market opens and kick-off, and OddsPortal works as an odds tracker for every match.

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. When a large number of casual bettors, often called “public” bettors, place money on one side, the line may shift to reflect this surge in interest. By shifting the line, they encourage bettors to wager on the opposite side, helping maintain even exposure on both outcomes.

If k is any positive number then X to Y is the same as kX to kY, and similarly if “to” is replaced with “in” or “for”. Multiplying these probabilities by 100% gives the percentage. 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.

Our experts rigorously test and only recommend sportsbooks that meet our high standards. 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 will pay are determined by the total amount that has been bet on all of the possible events.

Betting odds are usually expressed either as fractions (e.g. ‘3/1’) or as decimals (e.g. 4.0). All of these have different possibilities, probabilities, chances – or odds – betting sites not on gamestop of happening. They give you a quick indication of how much you could expect to win if your bet wins. Min £10 qualifying bets stake not returned. #AD BetBee is for new players aged 18 and over only. Cashback starts from your first completed deposit; future deposits add to the total, withdrawals deduct from it.

Moneyline, or American, odds are favoured by US bookmakers and punters, and are often expressed as positive and negative values (e.g. +250, -400). Bet £10+ on any sportsbook markets at odds of evens (2.00) or greater. “Double the odds” applies to fractional odds profits only, with extra winnings paid in cash on settlement. Get your initial stake back (up to £30) credited in set football markets.

Free bet valid 7 days from issue, usable on any Sport/Market as a 3+ fold ACCA with total odds 3.00–21.00, each leg 1.50+. Bonus funds are separate to cash funds and subject to 10x wagering requirement (bonus funds). #AD 18+ New players only. Opt in, deposit and bet £10 on any football market (odds 1/1+) within 7 days of sign up. Free bet – one-time stake of £50, min odds 1.5, stake not returned.