Odds Wikipedia
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.
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.
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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.
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. 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.
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Free stake not returned with winnings. Qualifying bets cannot be placed on a price boost. Qualifying bet must settle, excluding cash outs. Void/cashed out bets excluded. Place a first qualifying £10 bet at EVS (2.0) or greater using cash balance.
#AD 18+ UK Customers – Get 10% cashback on losses daily. Excludes cashout, E/W, Multis, Ineligible Markets & Odds Boosts. Free bet – one-time stake of £30, min odds 1.5, stake not returned. To qualify, place a min £10 bet from your cash balance at odds of EVS or higher—only your first bet counts, and it must not be voided or cashed out.
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 bookmakers 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.

