How to Read Betting Odds — Decimal & Fractional Guide

Reading betting odds is the single most important skill for any new sports bettor. Before you can make informed decisions about value, expected returns, or which bets to place, you need to understand exactly what the numbers on a sportsbook screen are telling you. This guide explains all three major odds formats in plain language, with real examples drawn from hockey and other sports popular with Canadian bettors.

Canadian sportsbooks use American odds (also called moneyline odds) by default, but you will also encounter decimal odds on European operators and fractional odds in horse racing markets. We cover all three, explain the conversion formulas used by every type of bet, and introduce implied probability — the concept that separates bettors who find value from those who simply guess.

By the end of this guide, you will be able to look at any odds format, calculate your exact potential return, understand what the sportsbook implies about a team’s chances, and identify when those implied chances may be wrong — which is where betting profit lives.

American Odds (Moneyline Odds) —

American odds are the standard on all major Canadian sportsbooks including 888sport, LeoVegas Sport, TonyBet Sport, Caesars, TooNieBet, and NorthStar Bets. They use positive and negative numbers to express two distinct things:

• Negative numbers (e.g. -150, -200, -110) indicate the favourite. The number tells you how much you must wager to profit C$100.
• Positive numbers (e.g. +130, +200, +350) indicate the underdog. The number tells you how much profit a C$100 stake returns.

Reading Negative American Odds

If you see Toronto Maple Leafs -160, the Leafs are the favourite. To calculate your profit, divide 100 by 160: you earn C$62.50 profit on every C$100 wagered. Or divide by the simplified ratio: a C$160 bet returns C$100 profit.

The formula: Profit = Stake ÷ (Odds / 100)

Example: C$50 bet at -160 → C$50 ÷ 1.60 = C$31.25 profit (C$81.25 returned total)

Reading Positive American Odds

If you see Ottawa Senators +140, the Senators are the underdog. A C$100 bet returns C$140 in profit (C$240 total). For other stake sizes, multiply by the odds divided by 100.

The formula: Profit = Stake × (Odds / 100)

Example: C$50 bet at +140 → C$50 × 1.40 = C$70 profit (C$120 returned total)

The -110 Standard

You will constantly see -110 in hockey totals, NHL betting spreads, and other markets. This is the standard "even-money" odds with the sportsbook margin baked in. On a -110/-110 total, you wager C$110 to win C$100. Both sides carry -110, which means the book collects C$220 from two bettors and pays C$210 to the winner, keeping C$10. This represents a 4.55% margin — the standard vig on even-money markets.

Some books offer reduced juice at -105 or even -102. At -105, you wager C$105 to win C$100. Over thousands of bets, this difference compounds significantly. Reduced juice books are worth seeking out for high-volume bettors.

Decimal Odds

Decimal odds are the most intuitive format for calculating exact returns because they represent your total payout per C$1 wagered, including your original stake. They are the default format in Europe, Australia, and on many European-founded Canadian sportsbooks. You will see decimal odds frequently when browsing soccer betting markets.

The formula: Total Return = Stake × Decimal Odds

And: Profit = Stake × (Decimal Odds - 1)

Decimal Odds Examples

Decimal odds above 2.00 indicate a team or outcome priced as an underdog. Below 2.00 indicates a favourite. Exactly 2.00 is true even money with no sportsbook margin — extremely rare in practice.

Fractional Odds

Fractional odds are expressed as a ratio, like 5/2 or 1/3. They are standard in UK sports betting and horse racing but less common on Canadian sportsbooks. Understanding all three formats is useful when comparing handicap betting markets across international platforms. The fraction tells you the ratio of profit to stake.

The formula: Profit = Stake × (Numerator ÷ Denominator)

Fractional Odds Examples

• 5/2: Profit C$5 for every C$2 staked. A C$10 bet returns C$25 profit + C$10 stake = C$35 total. (Equivalent to +250 American)
• 2/1: Profit C$2 for every C$1 staked. A C$10 bet returns C$20 profit + C$10 stake = C$30 total. (Equivalent to +200 American)
• 1/1: Profit equals your stake — true even money. (Equivalent to +100 American / 2.00 decimal)
• 1/2: Profit is half your stake. A C$10 bet returns C$5 profit + C$10 stake = C$15 total. (Equivalent to -200 American)
• 1/4: Heavy favourite. C$10 bet returns C$2.50 profit. (Equivalent to -400 American)

Converting Between Odds Formats

You will sometimes need to convert between formats when comparing sportsbooks or when a book only displays one format. Here are the conversion formulas for all three pairs.

Implied Probability: The Key to Finding Value

Implied probability is the conversion of odds into a percentage likelihood. It represents what the sportsbook believes is the chance of an outcome occurring, embedded in the price they offer. Understanding implied probability is what separates bettors who hunt for value from those who simply pick winners.

Implied Probability Formulas

For positive American odds: Implied Probability = 100 / (Odds + 100)

Example: +130 → 100 / (130 + 100) = 100 / 230 = 43.5%

For negative American odds: Implied Probability = |Odds| / (|Odds| + 100)

Example: -150 → 150 / (150 + 100) = 150 / 250 = 60%

For decimal odds: Implied Probability = 1 / Decimal Odds

Example: 2.30 → 1 / 2.30 = 43.5%

The Overround: Where the Vig Lives

If you add the implied probabilities of all outcomes in a market, the total will always exceed 100%. The excess is the sportsbook’s margin. On a standard hockey moneyline with the favourite at -160 and the underdog at +130:

• Favourite implied probability: 160 / 260 = 61.5%
• Underdog implied probability: 100 / 230 = 43.5%
• Total: 105% — the extra 5% is the book’s margin

This means the book prices the market so that, over many bets, they collect more than they pay out. Your goal as a bettor is to identify cases where the sportsbook’s implied probability is wrong — where the true probability of an outcome is higher than their odds suggest. That gap is positive expected value, and it is where long-term profit originates. For a practical example of this concept in action, see our hockey betting guide.

Odds Shopping: Why the Same Bet Pays Differently Everywhere

Different sportsbooks set different odds on the same event. The Toronto Maple Leafs might be -145 at 888sport and -155 at Caesars for the same game. Over a season of hockey betting, consistently finding the best price on your bets can add 3 to 7% to your overall return — a meaningful edge on top of your selection process.

Having accounts at multiple licensed Canadian sportsbooks and comparing prices before each bet is called line shopping. It requires more time but directly improves profitability without any additional analytical skill. Player prop markets show the largest price differences between books — sometimes 20 to 30 cents on the same prop — making props the highest-value market for line shoppers. This is especially true for NFL betting props and live betting markets where odds shift rapidly.

Odds Movement: Reading the Market

Sportsbooks open lines based on their own models and adjust them based on incoming bets and new information. Understanding why lines move — and in which direction — is an advanced skill that adds another layer to your betting analysis.

Lines move toward the side receiving more money (or more specifically, more sharp money from professional bettors). If Ottawa opens at +150 against Toronto and moves to +130, it means bettors are backing Ottawa, shortening their price. This typically signals one of three things: sharp bettors like Ottawa’s value at the opening number; injury news favours Ottawa; or the public is betting Toronto heavily enough to move the line despite the book’s preference to balance action.

Reverse line movement is especially significant: when a team receives heavy public betting but the line moves against them, it usually indicates that sharp money is on the other side. This is one of the clearest signals of professional betting activity available to recreational bettors. When you spot a favourable line move, having a betting bonus in your account lets you take advantage with less personal capital at risk. Some sportsbooks like Caesars Sportsbook also let you cash out before the game ends if the line continues moving in your favour after you have placed the bet.

Frequently Asked Questions