How betting odds work: what they are and how to use them
Make your first deposit of £10+, then place a £10 single bet from main balance at odds of EVS+ (2.00+) on any sports market (excluding Virtuals). As a result, the term has more historical than literal accuracy in today’s global betting market. 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.
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.
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. Odds can also be expressed as a number, by dividing the terms in the ratio—in this case it is unique (different fractions can represent the same rational number).
The total of these three percentages is 100%, thus representing a fair ‘book’. In a 3-horse race, for example, the true probabilities of each of the horses winning based on their relative abilities may be 50%, 40% and 10%. In formulating the odds to display the bookmaker will have included a profit margin which effectively means that the payout to a successful bettor is less than that represented by the true chance of the event occurring. In gambling, the odds on display do not represent the true chances (as imagined by the bookmaker) that the event will or will not occur, but are the amount that the bookmaker will pay out on a winning bet, together with the required stake. In most cases, the favorite will have negative moneyline odds (less payoff for a safer bet) and the underdog will have positive moneyline odds (more payoff for a risky bet).
Whether it’s choosing the top online casinos in the US or the best online casinos in Canada, non gamstop bookmakers we help you play with confidence across slots, tables, live dealer games, and more. Convenience is key, while reliability, functionality, live streaming, abundance of betting markets, and features are king. 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.
In tennis we follow the ATP and WTA tours every week, the Challenger and ITF events in between and the four Grand Slams, from the Australian Open to Wimbledon and the US Open. For beginners, our bet calculator shows the payout of a bet, for a single or an accumulator, in decimal, fractional or American 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.
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. If you bet $10 at 7/2, you’d get $35 in profit plus your initial $10 back, totaling $45. They’re expressed as fractions, like 5/1 or 7/2, showing the ratio of profit to the original stake. Decimal odds make comparing bets straightforward because you’re seeing the total return value in one number. Higher numbers indicate higher potential payouts, while lower numbers signify favorites and lower returns relative to the stake. The key to understanding decimal odds is that they directly represent the total return.
If you see +250, that team is the underdog; a $100 bet would return $250 if they win. 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.
If you do have any concerns about gambling please contact GambleAware We are a team of software developers and experienced Matched Bettors, dedicated to helping you earn a sustainable, tax-free income every month. Plus, that gives you the opportunity to take advantage of the bookmakers’ bonuses and earn free cash.