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

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).

Plus, that gives you the opportunity to take advantage of the bookmakers’ bonuses and earn free cash. The issue with betting odds is that they’re always tipped in the bookmakers’ favour to allow them to make a profit. Because of the many factors involved, it is impossible to calculate exact probability in sports betting. In betting terms, probability is odds expressed as a percentage.

For example, «odds of a weekend are 2 to 5», while «chances of a weekend are 2 in 7». Implied by this definition is the fact that the probability of an event is given by the ratio of favourable outcomes to the total number of possible 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».

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. Sports information services are often used by professional and semi-professional sports bettors to help achieve this goal. It was about 3.7% less for wins by the visitors, and 5.7% less for draws. A study on horse racing betting not on gamstop soccer betting found that the probability for the home team to win was generally about 3.4% less than the value calculated from the odds (for example, 46.6% for even odds). The total of these three percentages is 100%, thus representing a fair ‘book’.

Moneyline odds use $100 as the evens line, with either positive or negative outcomes. If you’d like a bit more guidance, we have a full guide on how fractional odds work in betting. You may also see odds expressed with the lowest number first e.g. 1/2 or 2/7. Once you understand betting odds and the differences between them, reading them becomes easy. Fractions were traditionally used to bet on horse racing and were most popular in high street betting shops in the UK, before the advent of internet gambling. Betting odds are usually expressed either as fractions (e.g. ‘3/1’) or as decimals (e.g. 4.0).

This is a difficult task considering the huge teams of mathematicians that they employ. 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.

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). A «moneyline» wager refers to odds on the straight-up outcome of a game with no consideration to a point spread. For example, 6/5 fractional odds (also described as «1.2» or «6 to 5») are the same as 11/5 decimal odds (also described as 2.2 or «11 for 5). A variation of fractional odds is known as Hong Kong odds. However, not all fractional odds are traditionally read using the lowest common denominator (i.e. simplifying the fraction when possible).

Our basketball odds page brings together the games of the day, while results and standings go back several seasons. On the blocked odds page, you will be able to see matches or markets that online bookmakers are no longer offering odds for, which can signal a change in the market before other operators react to it. It is where the hot odds of the day show up first, and you can filter it by the last hour, 12 hours or 24 hours, by the percentage of bookies cutting their price and by market. The dropping odds page shows when the odds on a team, player or market have dropped before the start of a match.