Understanding betting odds is the foundation of informed combat sports betting. This tutorial explains every odds format, how to calculate implied probability, and how to identify value in UFC and MMA markets.
What Are Betting Odds?
Betting odds represent the probability of an outcome and determine how much you win relative to your stake. Every sportsbook displays odds, but the format varies by region. The three main formats are decimal (Europe, Australia), American (United States), and fractional (United Kingdom).
All three formats express the same information differently. Learning to read all three gives you flexibility when comparing odds across international sportsbooks.
Decimal Odds
Decimal odds are the simplest format. The number represents your total return per unit staked, including your original stake.
Decimal odds of 2.50 mean you receive €2.50 for every €1 staked — €1.50 profit plus your €1 stake back. Decimal odds of 1.40 mean you receive €1.40 for every €1 staked — €0.40 profit.
The favourite always has lower decimal odds. The underdog always has higher decimal odds. Decimal odds of 2.00 represent an exactly even proposition — a 50/50 chance according to the bookmaker.
American Odds
American odds use positive and negative numbers. Negative odds show how much you must stake to win €100. Positive odds show how much you win on a €100 stake.
-200 means you stake €200 to win €100 profit. +150 means you stake €100 to win €150 profit. The favourite has negative odds. The underdog has positive odds.
Fractional Odds
Fractional odds show your profit relative to your stake. 5/2 means you win €5 for every €2 staked. 1/4 means you win €1 for every €4 staked.
Converting Between Formats
Decimal to implied probability: divide 1 by the decimal odds. Odds of 2.50 = 1/2.50 = 0.40 = 40% implied probability.
American to implied probability: For negative odds, divide the absolute value by (absolute value + 100). -200 = 200/(200+100) = 66.7%. For positive odds, divide 100 by (odds + 100). +150 = 100/(150+100) = 40%.
Identifying Value
A bet has value when the true probability of an outcome is higher than the implied probability of the odds. If your analysis suggests a fighter has a 55% chance of winning but the odds imply only 40%, that is a value bet.
Compare odds at Vulkan.bet and Legendz to find the best available prices.
The Bookmaker Margin
Sportsbooks build a margin (also called vig or juice) into their odds. If the true probability of two outcomes is 50/50, the bookmaker might price both at 1.90 instead of 2.00. The difference is their profit margin. Understanding this helps you identify which sportsbooks offer the best value.
Frequently Asked Questions
*What odds format is best for beginners?* Decimal odds are the simplest to understand and calculate. Start with decimal and learn the others as you gain experience.
*How do I calculate my potential profit?* With decimal odds: multiply your stake by the odds, then subtract your stake. A €10 bet at 2.50 = €25 total return = €15 profit.
*What does -110 mean in UFC betting?* -110 means you need to stake €110 to win €100 profit. This is close to even money with a small bookmaker margin.
*Can odds change after I place my bet?* Your bet is locked at the odds when you placed it. Subsequent odds movements do not affect your bet.
*Why do different sportsbooks have different odds?* Each sportsbook sets its own odds based on their risk assessment and the bets they have received. This is why comparing odds across platforms is essential.
About the authors
AiRingside Editorial Team
AiRingside is an independent combat sports publisher. Every tutorial is researched, written, and reviewed before publication by our editorial team.
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