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

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). All of these have different possibilities, probabilities, chances – or odds – of happening.

Sharp action – bets placed by professional or experienced bettors – also triggers line movement. When a large number of casual bettors, often called “public” bettors, non gamstop betting sites place money on one side, the line may shift to reflect this surge in interest. By shifting the line, they encourage bettors to wager on the opposite side, helping maintain even exposure on both outcomes.

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. The same price is 3/1 in fractional odds and +300 in American odds, which means a 100 bet wins 300 on top of the stake. This is a difficult task considering the huge teams of mathematicians that they employ.

This code is for marketing and tracking purposes only. He is an NCTJ-qualified sports journalist who has accumulated over 10 years of experience in the sports betting industry. 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.

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. Higher numbers indicate higher potential payouts, while lower numbers signify favorites and lower returns relative to the stake.

However in many situations, the possible loss (“stake” or “wager”) is paid up front and, if the gambler wins, the net win plus the stake is returned. 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.

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.

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. Get your initial stake back (up to £30) credited in set football markets. Free bets valid 7 days from individual release, stake not returned, no cash out. To qualify for free bets, the new user must place and settle £20 on easyBet markets and use the bonus code EB20.

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.