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

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.

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 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). 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).

From local leagues to international tournaments, our website shows the top price for every outcome before you bet. OddsPortal is a free odds comparison site where you can compare betting odds from leading bookmakers on every match. Odds comparison, also known as line shopping, means checking the price of the same outcome at several bookmakers and taking the highest one. With results, standings, predictions and the best odds on the same site, you can check the top price before every bet. We also compare prices on boxing and MMA, where big fights are added as soon as bookmakers publish odds, on esports and on rugby union, rugby league, baseball, volleyball, Aussie rules and many more. Our tennis odds page compares the prices on every match of the day, next to past results and the odds they closed at.

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. The value bets page compares the odds of each bookmaker with the average odds for the same outcome, highlighting the markets where one price stands out, with the probability included. OddsPortal has a number of betting tools that can bring your attention to interesting markets you may never have thought about betting on before, always with the best available price.

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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. 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 numerator and denominator of fractional odds are often integers, thus if the bookmaker’s payout was to be £1.25 profit for every £1 stake, this would be equivalent to £5 profit for every £4 staked, and the odds would therefore be expressed as 5/4. 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 uk betting sites NHL, the SHL in Sweden and the KHL among many hockey leagues, with prices on single games and on the outright winners.

By shifting the line, they encourage bettors to wager on the opposite side, helping maintain even exposure on both outcomes. They range from player stats, like total points scored by a star player, to quirky events like the length of the national anthem. Prop bets, short for proposition bets, focus on specific events or outcomes within a game, rather than the final score. Since these bets can be made months in advance, they offer a chance for big payouts, especially when backing underdogs.