Betting Odds Explained The Complete Guide 2026

Odds-on is a phrase that simply implies that the chosen market will pay out less than double the amount of your stake if it is a winner. The list of bookmakers on these sites is not exhaustive, but there are many included on the best sites and this is the quickest and most effective way to ensure you get the best price for your bet. If you were to bet £10 on that outcome, you would gain £20 more in returns at the price of 7/1, compared to 5/1. And when online betting, you can take advantage of these differences to make sure you get the best price on offer. The reason for this is simply that despite bookmakers’ odds being similar for most markets, sometimes when individual bookmakers calculate odds, they will offer different prices. Many bookmakers still employ one or more people to oversee this process and they may make small adjustments to the odds to make their book balance, or to offer customers a special deal on a selection or similar.

• The number you see is how much you’ll win for every £1 you bet.
• Fractional odds are widely used in the UK, but they are also the most common odds format on U.S. horse racing.
• If you calculate the book percentage on a bookmaker’s odds it will normally be over 100%.
• Putting these odds into the odds converter will bring the calculation to a probability percentage of 33.33 per cent.
• Our odds converter works automatically and in an instant, so you can quickly get the odds that you need.

First single & E/W bet only. Registration required. Returns exclude Bet Credits stake. What ever type of bet you would like to place, from accumulators to Super Yankees, we have you covered! To begin, select from 30+ calculator types. As all professional gamblers will tell you, in order to make a long-term profit, you will need to consistently find ‘value’.

Presence to absence ratio

One of the easiest to understand is decimal odds. If you place a bet, you can come across different ways of showing the odds. For more information about betting exchanges and how to use them, visit our betting exchanges page.

This is the minimum sample size you need in the absence group to estimate the true population odds ratio with the required relative precision and confidence level. This is what you expect the odds ratio to be, i.e., the odds of the outcome given presence of the property you are looking for an association with relative to the same outcome in the absence of that property. Note that the actual precision achieved after you collect your data will be more or less than this target amount, because it will be based on the odds ratio and prevalence observed in the data and not the expected values supplied to the calculator. The relative precision is the percentage by which the lower limit for your confidence interval is less than the estimated odds ratio. Try changing the five inputs (the relative precision, confidence level, absence case prevalence, expected odds ratio and presence to absence ratio) to see how they affect the sample size. If we would like to estimate the odds ratio with 95% confidence and a relative precision of 50%, how many samples are required?

That’s why it’s important to think long-term and bet with a clear plan. These odds often indicate the smart money is watching closely, and if late market moves come in, they can shorten quickly. These odds suggest the result is plausible, but not expected by the masses—often a signal of potential value for informed punters. If the chances are roughly 32% though (or lower), then it might not be such a great bet. Decimal and American odds express the same thing—just in different styles—in each case the numbers above all represent exactly the same odds. An unbiased coin is usually flipped at the start of a sports match.

Larger parlays are less likely to win but generate larger payouts when they do. Visit bet365.com to check out their Soccer parlay builder, remembering to enter the bet365 bonus code if joining for the first time. Works for all sports, including baseball, NFL, MMA and more. In general, the higher the response rate the better the estimate, as non-response will often lead to biases in your estimate. Multiply this number by the sampling ratio to calculate the sample size for the presence group.

✅ How to Approach 21/10 Bets – Summary

But what do these bets really mean for you? By the end, you’ll be ready to tackle rugby betting like a pro. Understanding odds is the key to becoming a savvy rugby bettor. Rugby betting is all about making the games even more exciting, and you’re right in the heart of it! Whether you’re a casual punter or aiming to bet with an edge, recognising the real story behind the odds is what separates guesswork from strategy.

If you’re trying to profit long-term, avoid chucking a fiver on a 21/10 shot just because it “looks good.” Casual bets drain your bankroll faster than you think. Because bets at 21/10 only win about 1 in 3 times on average, your strategy needs to survive losing runs. Betting at 21/10 can offer good returns, but only if you believe the true probability of your selection winning is higher than 32.26% (the implied probability). For smart punters, 21/10 can signal a sweet spot—the kind of price where informed betting and good judgement can turn long-term profit. In racing, 21/10 odds usually reflect a second or third favourite in the betting.

In practice, this means that while No Vig odds provide a more accurate reflection of probability, they may still skew slightly over-pricing favourites and under-pricing outsiders. This bias refers to the tendency for bookmakers to offer poorer prices on longshots over favourites compared to their real chance of winning. To use it, input the real odds for each selection, and the calculator will show the No Vig odds and the implied probabilities, ensuring that the total book percentage is always 100%. The No Vig Calculator helps bettors determine the “fair” or “true” odds for a set of selections by removing the bookmaker’s margin (vig). It is not commonly used nowadays, as most bookmakers’ odds are computerised, but it uses a series of gestures of the hands and arms to signify the odds of certain runners in the race.

You can make these types of calculation to assess the % chance you think your selection has of achieving the result you are betting on and see if you feel the odds are giving you enough value to make the bet. The concept of implied probability is worth keeping in mind when you try to assess the value of probability calculator odds from a bookmaker. With any negative moneyline figure beyond -100 the price is odds against and you stand to make less profit than the stake amount. Again, if the moneyline figure is positive it tells you what you can win on a successful bet with a £100 stake.