Understanding Football Betting Odds: Fractional, Decimal, and American Formats

Understanding Football Betting Odds: Fractional, Decimal, and American Formats

If you’re getting into football betting, one of the first—and most important—things you need to understand is betting odds. Odds tell you how much money you stand to win from a bet, and they also represent the implied probability of an outcome.

There are three main formats used in betting: Fractional, Decimal, and American (Moneyline). While they all serve the same purpose, each one is expressed differently, and which format you see often depends on where you’re betting.

This guide breaks down each type of odds, how to read them, how to calculate potential winnings, and when each is typically used.

---

What Are Betting Odds?

At their core, betting odds serve two purposes:

1. To indicate the likelihood (or implied probability) of a particular outcome

2. To show how much you can win relative to your stake

For example, if a team is given odds of 2.00 (decimal), the bookmaker believes there’s a 50% chance of that team winning. If you bet $10, your total return would be $20 (including your stake).

---

1. Fractional Odds (e.g., 5/1)

Where it’s used: Most common in the UK and Ireland

Fractional odds are displayed as a fraction, such as 5/1, spoken as “five to one.” This means:

• You win $5 for every $1 you stake.

• Your total return would be $6 ($5 profit + $1 original stake).

Example:

• Odds: 5/1

• Stake: $10

• Winnings: $50

• Total return: $60

If the odds were 1/5, it means you’d win $1 for every $5 staked—a heavy favorite.

How to calculate implied probability:

Implied Probability=DenominatorNumerator + Denominator×100Implied Probability=Numerator + DenominatorDenominator​×100

So, for 5/1:

15+1×100=16.67%5+11​×100=16.67%

---

2. Decimal Odds (e.g., 2.50)

Where it’s used: Popular in Europe, Canada, Australia, and increasingly online globally

Decimal odds are arguably the easiest to understand. They show the total return for every $1 bet, including your stake.

Example:

• Odds: 2.50

• Stake: $10

• Winnings: $15

• Total return: $25 (because 10 x 2.50 = 25)

Decimal odds are particularly user-friendly because you can instantly calculate your return just by multiplying your stake by the odds.

How to calculate implied probability:

Implied Probability=1Decimal Odds×100Implied Probability=Decimal Odds1​×100

For 2.50:

12.50×100=40%2.501​×100=40%

---

3. American Odds (e.g., +200 or -150)

Where it’s used: Standard in the United States

American odds are based around winning or staking $100 and are divided into two types:

• Positive Odds (e.g., +200): Indicates how much you’d win on a $100 bet.

• Negative Odds (e.g., -150): Indicates how much you need to stake to win $100.

Positive Example (+200):

• You win $200 for every $100 staked.

• Stake: $100 → Winnings: $200 → Total Return: $300

Negative Example (-150):

• You need to bet $150 to win $100.

• Stake: $150 → Winnings: $100 → Total Return: $250

How to calculate implied probability:

• For positive odds:

Implied Probability=100Odds+100×100Implied Probability=Odds+100100​×100

So for +200:

100200+100×100=33.33%200+100100​×100=33.33%

• For negative odds:

Implied Probability=−Odds−Odds+100×100Implied Probability=−Odds+100−Odds​×100

So for -150:

150150+100×100=60%150+100150​×100=60%

---

Converting Between Odds Formats

If you want to switch between odds types, there are standard formulas you can use. But most online sportsbooks allow you to change the odds display in your account settings.

• Fractional to Decimal:

  Decimal=(NumeratorDenominator)+1Decimal=(DenominatorNumerator​)+1

• Decimal to American:

  • If Decimal ≥ 2.00:

    $$\text{American}=(\text{Decimal}-1)\times 100$$

  • If Decimal < 2.00:

    $$\text{American}=-100/(\text{Decimal}-1)$$

---

Which Format Is Best?

There’s no “best” format—just what’s most familiar or convenient for you:

• Use fractional if you’re in the UK or following UK bookmakers.

• Use decimal for simplicity, especially if you’re betting across multiple sports or platforms.

• Use American if you’re in the U.S. or betting on platforms like FanDuel or DraftKings.

---

Final Thoughts

Understanding how football betting odds work is essential before placing a single bet. Not only do they tell you how much you stand to win, but they also reveal what the bookmaker believes about a team’s chances.

Whether you’re backing an underdog at +300 or calculating value in a 1.80 decimal odd, knowing how to read odds helps you make informed, strategic decisions—and gives you a significant edge in football betting.

So before you dive into your next wager, take a second to look at the odds—and now, you’ll know exactly what they’re telling you.