Top Tips for Understanding Betting Lines
04-11-2023

If you’ve ever wondered how the betting line works, why the odds look different on some websites, or what the implied probability rate means, you’ve come to the right place.
Here are several top tips for understanding betting lines and the implied probability rate based on the odds you are given.
How to understand betting lines
In sports betting, there are three different betting formats – American/moneyline odds format, which is more commonly used in North America (the US and Canada), fractional odds (mostly used in the United Kingdom), and decimal odds (used in most other countries).
Line betting is when the online bookmaker handicaps a sporting event to give one of the sides/players more favourable odds.
For example, suppose a sports betting operator believes there is a 4.5 difference between the two sports stars or teams competing against each other. In that case, you can place a wager on one team to win by over 4.5 points or bet on the opposing player/team to lose by less than 4.5 points.
Regarding the ‘line’ (the negative symbol or -) in the American/moneyline odds format, it indicates the odds-on favourite for that particular event (the player/team most likely to win).
The number following the negative symbol is the odds, which tells you how much to wager for every $/€/£100 you want to win. In other words, if the favourite sports person or team is priced at -120, you would need to place a $/€/£120 (or equivalent currency value) wager to win $/€/£100.
It sounds a lot more complicated than it is, but to place the
best bet of the day, you must familiarise yourself with the different odds formats.
What’s the implied probability rate?
When you convert the odds into a percentage of a certain outcome actually occurring, you have the IPR (implied probability rate). In other words, something with only 1.00% IPR is extremely unlikely to occur. On the other hand, something with a 99.00% IPR will almost certainly happen.
However, the returns on a bet with only a 1.00% IPR would be huge, and the returns on something that’s basically guaranteed would be tiny. It’s the same in
football, cricket, tennis, and all other sports.
A look at a few examples
Let’s take a quick look at a few examples of bets in all three formats, showing the IPR and how much you can win based on your bet size.
- The odds-on favourite might be priced at 1.01 (decimal odds), 1/100 (fractional), or -10,000 (American/moneyline). These odds all mean the same. It also means this outcome has a 99.00% implied probability rate. Therefore, if you bet $/€/£100 with these odds, your total returns would be $/€/£101.00, which includes only a $/€/£1.00 profit, plus your initial $/€/£100.00 stake returned
- If you place a $/€/£100.00 wager on a bet with a 50% chance of occurring (IPR), the odds would appear as 2.00 (decimal), 1/1 (fractional), or +100 (American/moneyline), and you win, you would double your money. Your total returns would be $/€/£200, including your $/€/£100.00 profit and your initial $/€/£100 stake returned.
- If you place a $/€/£100.00 wager on a bet with a 1.00% chance of occurring (IPR), the odds would appear as 101.00 (decimal), 100/1 (fractional), or +10,000 (American/moneyline), and you win, your total returns would be $/€/£10,100, including your $/€/£10,000.00 profit and your initial $/€/£100 stake returned
Final note
Some websites allow you to change which format you would prefer to display the odds in. If you can get to grips with what the odds and the implied probability rates are trying to tell you, it can help you place strategic bets that are more likely to win (but never guaranteed, don’t forget).