How to Read Betting Odds
Written by the DawBets analytics team · Updated April 2026 · 8 min read
Odds tell you two things: how much you'll win and how likely the sportsbook thinks an outcome is. Mastering odds formats is the first step to spotting value.
Quick answer
Betting odds show your potential profit and the implied probability of an outcome. American odds use +/- notation (positive = underdog profit on $100, negative = how much to risk for $100 profit). Decimal odds multiply your stake. All formats encode the same information — pick whichever is most intuitive.
American odds (+/- format)
American odds are the standard format at US sportsbooks. They come in two flavors: positive and negative.
Negative odds (-) represent favorites. The number tells you how much you need to bet to win $100. At -200, you'd wager $200 to win $100 profit (total return of $300).
Positive odds (+) represent underdogs. The number tells you how much you'd win on a $100 bet. At +200, a $100 bet returns $200 in profit (total return of $300).
-110: Bet $110 to win $100 → total return $210
+100: Bet $100 to win $100 → total return $200 (even money)
+150: Bet $100 to win $150 → total return $250
+300: Bet $100 to win $300 → total return $400
The most common odds you'll see are around -110 on both sides of a spread or total. That -110/-110 split is the sportsbook's standard margin — each side pays slightly less than even money.
Decimal odds
Decimal odds are popular in Europe, Canada, and Australia. They represent your total return per dollar wagered, including your original stake.
Decimal 1.50 = Bet $100, return $150 (= $50 profit)
Decimal 1.91 = Bet $100, return $191 (= $91 profit, ≈ -110 American)
The conversion is straightforward:
Positive: (+150 / 100) + 1 = 2.50
Negative: (100 / 110) + 1 = 1.909
Decimal to American:
If decimal ≥ 2.0: (decimal - 1) × 100 = American positive
If decimal < 2.0: -100 / (decimal - 1) = American negative
Decimal odds make calculating parlay payouts easier — just multiply all the decimal odds together. DawBets lets you toggle between American and decimal display in your settings.
Converting odds to implied probability
Every set of odds implies a probability — what the sportsbook's price says about how likely the outcome is. This is the most important concept for finding value.
Negative: -150 → 150 / (150 + 100) = 60.0%
Positive: +200 → 100 / (200 + 100) = 33.3%
Decimal to implied probability:
1 / decimal odds = implied probability
1 / 2.50 = 40.0%
If you believe a team has a 45% chance of winning but the odds imply only 40%, that's a +EV bet — the sportsbook is underestimating the true probability. This is the foundation of expected value betting.
The vig: why probabilities add up to more than 100%
If you convert both sides of a two-way market to implied probabilities, they'll add up to more than 100%. That extra margin is the vig (vigorish), also called juice or the overround.
Team B: -110 → 52.38% implied
Total: 104.76% (the extra 4.76% is the vig)
The vig guarantees the sportsbook profits over time. On a -110/-110 market, a bettor betting one side has a roughly 2.4% disadvantage before the game even starts.
Removing the vig — called devigging — is how you estimate the true fair probability. DawBets automatically devigs every market using odds from 20+ sportsbooks to determine which bets have a genuine mathematical edge.
Comparing odds across sportsbooks
Different sportsbooks set different odds for the same event. One book might have the Bills at +155 while another has them at +145. That 10-cent difference directly impacts your expected return.
This is why line shopping — checking multiple books to find the best price — is one of the highest-impact habits a bettor can develop. The DawBets odds comparison tool shows real-time prices from every major sportsbook side by side.
Even small differences compound. Getting +155 instead of +145 on every underdog bet over a season adds up to thousands of dollars in additional profit for active bettors.
DawBets tracks real-time odds across 20+ sportsbooks to find positive expected value edges.
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Open the odds comparison tool — freeFrequently asked questions
What does -110 mean?
It means you need to bet $110 to win $100 in profit. This is the standard vig line used by most sportsbooks on spreads and totals. The implied probability is about 52.4%, meaning you need to win more than 52.4% of your bets at -110 to be profitable.
Are decimal odds better than American odds?
Neither format is "better" — they convey the same information. American odds are standard in the US. Decimal odds are simpler for calculating parlays (just multiply) and are more intuitive for understanding total return. DawBets supports both formats.
Why do odds change before a game?
Odds move based on betting action (money coming in on one side) and new information (injuries, weather, lineup changes). Sportsbooks adjust to balance their risk and respond to sharp bettors. This is why timing matters and why live odds comparison is valuable.
What is "even money"?
Even money means you win exactly what you risked — +100 in American odds or 2.00 in decimal. A $100 bet at even money returns $200 total ($100 profit + $100 stake). True even-money lines are uncommon because the vig usually pushes both sides below +100.