As we have mentioned, the way that you figure out the return you get from winning a bet and the likelihood of that event happening depends on the odd format. There are three main odd formats used for Dota 2 betting, including Decimal odds, Fractional odds, and American odds.
However, the most popular ones for esports betting are the Decimal and Fractional odds, and you won't be seeing American odds used for Dota 2 betting that often.
With the Fractional format, odds are expressed using a fraction with two numbers, like 5/2, which is pronounced five to two. The second number represents your betting amount, and the first number represents the amount of return you will get if you make a bet worth the second number.
The Decimal format uses a number with a decimal to express odds like 5.0 or 3.0. This number represents the exact multiple of the betting amount you will get in return. For example, if you win a bet with 5.0 odds after betting $10, you will get a total of $50 in return, with $40 being your winnings.
While these are not that common for Dota 2 betting, you might occasionally come across them. American odds are expressed with a number and either a positive or a negative sign. For example, -120 or +190. The number with the negative sign represents the amount you need to bet to win $100. On the other hand, the number with the positive sign represents the amount you will win if you bet $100.
Odds and Likelihood
Odds also tell you the likelihood of the outcome actually occurring. Outcomes with odds that give you a high return have fewer chances of occurring. On the other hand, the ones with odds that give you low returns have high chances of occurring.