Understanding Sports Betting Odds
Sportsbook odds tell you two things: the implied probability of an outcome and how much you stand to win. Louisiana sportsbooks default to American odds, but most apps let you switch to decimal or fractional in settings.
American odds (default in Louisiana)
American odds use plus and minus signs. Negative odds (e.g. -150) show how much you need to stake to win $100. Positive odds (e.g. +130) show how much you win on a $100 stake. -150 means risk $150 to win $100; +130 means risk $100 to win $130.
Decimal odds
Decimal odds (e.g. 2.50) include your stake in the payout. Multiply your stake by the decimal to get your total return: a $10 bet at 2.50 returns $25 ($15 profit + $10 stake back). Decimal is the global default used by European books like bet365.
Fractional odds
Fractional odds (e.g. 3/2) show profit per unit staked. 3/2 means win $3 for every $2 risked. Fractional is most common in horse racing and UK soccer markets.
Converting between formats
All three formats describe the same payout. Most Louisiana sportsbook apps include a toggle in account settings. As a rule of thumb: American -150 = decimal 1.67 = fractional 2/3. American +200 = decimal 3.00 = fractional 2/1.
Implied probability
Every odds line implies a probability of the outcome. -150 implies about 60% probability of winning; +200 implies about 33%. Sportsbooks bake in a margin ("vig" or "juice"), so the implied probabilities of both sides typically sum to slightly over 100%.
FAQ
Why are odds shown with plus and minus?
American odds use plus and minus to indicate underdog and favorite. Minus = favorite (more likely to win, smaller payout per dollar). Plus = underdog (less likely, bigger payout per dollar).
What does "vig" mean?
Vig (or juice) is the sportsbook's built-in margin. Standard NFL spread bets are priced at -110 on both sides; that means you risk $110 to win $100, and the extra $10 is the book's edge.