How to Read Betting Odds

American Odds: The Canadian Default

Ontario sportsbooks display American odds by default. A minus number is the favourite: -150 means you risk C$150 to win C$100 profit, or equivalently C$15 to win C$10. A plus number is the underdog: +130 pays C$130 profit per C$100 staked. The bigger the minus number, the heavier the favourite; the bigger the plus number, the longer the shot.

The mental conversion worth memorizing is odds to probability. Favourites: odds divided by odds plus 100, so -150 is 150/250, or 60%. Underdogs: 100 divided by odds plus 100, so +130 is 100/230, or 43.5%. When you see -110, think 52.4%, because that number is the break-even rate for the most common price in sports betting.

Decimal and Fractional Formats

Decimal odds, standard in Europe and Australia and available as a display option in every Canadian app, show your total return per unit staked, stake included. Odds of 1.91 return C$191 on a C$100 bet; odds of 3.50 return C$350. Anything below 2.00 is a favourite, anything above is an underdog, and implied probability is simply 1 divided by the odds.

Fractional odds, the old British racing format, show profit over stake: 5/2 means C$5 profit per C$2 staked, which is decimal 3.50 or +250. You will mainly meet fractions on horse racing feeds. For quick conversions: decimal equals the fraction plus 1, and American plus odds equal the fraction times 100.

Pick one format and standardize. Most bettors doing any math switch their app to decimal because payout and probability calculations become single steps. Reading a line like Leafs -1.5 (+170), ML -150, O/U 6.5 (-105/-115) then becomes automatic: handicap or total first, price in brackets second.

A Worked Example Off a Real Board

Take a Saturday NHL board entry: Canucks +120 at Flames -140, total 6.0, over -110, under -110. Reading it: Calgary is the favourite, 140/240 = 58.3% implied. Vancouver is 100/220 = 45.5%. The sum is 103.8%, so the book's margin on this moneyline is modest. The total is a coin flip priced at standard juice.

Now apply money. C$50 on the Canucks at +120 returns C$110 (C$60 profit). C$50 on the Flames at -140 returns C$85.71 (C$35.71 profit). If another book lists Vancouver at +125, that identical bet returns C$62.50 instead of C$60. Reading odds fluently is what makes those comparisons instant, and the comparisons are where the money is.