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

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.

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). 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.

OddsPortal is a free odds comparison site where you can compare betting odds from leading bookmakers betting sites 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. 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.

For instance, if the line is 220.5 in an NBA game, you’d bet on whether the teams’ combined score will be over 220 or under 220.5. Totals bets, also known as Over/Under bets, focus on the combined score of both teams rather than who wins. Point spread bets are all about leveling the playing field between teams, making any game more exciting.

The same selection is priced differently by each bookmaker, so comparing bookmaker odds is the simplest way to make sure a winning bet pays out as much as possible.

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.

A sports betting odds comparison that only shows the current price for the home win, draw and away win tells you less than one that also shows the opening odds and the payout of each bookie. The hockey odds page lists the next games with the best price for each team, next to recent results and standings. The fact that bookmakers have large teams of maths experts working out odds means that beating them at their own game can be very difficult. Our odds page features top-rated sportsbooks in your area, providing the most up-to-date lines for every game and futures market across various sports. These bets can cover anything from team milestones to individual performances, making games more interactive and fun. Futures keep you invested throughout the season, adding suspense as teams rise or fall and turning each game into a step toward your bigger prediction.

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. 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. We have all the best resources for you to get started on your sports betting journey