How to Read American Odds: A Beginner’s Guide for US Sports Bettors

If you’ve ever opened a US sportsbook and seen a matchup listed as -150 next to one team and +130 next to the other, you’ve run into American odds — the standard format for sports betting across the United States. They look cryptic at first, but the logic behind them is simple once it clicks, and understanding it is the single most useful skill you can build before placing your first bet.

What the plus and minus actually mean

American odds always describe a bet relative to $100:

• A minus number (e.g. -150) tells you how much you need to stake to win $100. A -150 favorite means you’d risk $150 to win $100 in profit.
• A plus number (e.g. +130) tells you how much you’d win on a $100 stake. A +130 underdog means a $100 bet returns $130 in profit if it hits.

The favorite always carries the minus sign, and the underdog always carries the plus sign. The bigger the minus number, the heavier the favorite; the bigger the plus number, the longer the underdog’s odds.

Calculating your actual payout

You rarely bet exactly $100, so here’s the math scaled to any stake:

For negative (favorite) odds

profit = stake × (100 ÷ |odds|)

Example: a $50 bet at -150 → 50 × (100 ÷ 150) = $33.33 profit (plus your original $50 back).

For positive (underdog) odds

profit = stake × (odds ÷ 100)

Example: a $50 bet at +130 → 50 × (130 ÷ 100) = $65 profit (plus your original $50 back).

Implied probability: the number sportsbooks don’t show you

Every odds line encodes a probability estimate. Converting odds to implied probability is how you judge whether a bet actually offers value, rather than just picking whoever you think will win.

• Negative odds: implied probability = |odds| ÷ (|odds| + 100)
• Positive odds: implied probability = 100 ÷ (odds + 100)

A -150 favorite implies a 60% win probability. A +130 underdog implies a 43.5% win probability. Add those two together and you’ll notice they sum to more than 100% — that gap is the sportsbook’s built-in margin, often called “the vig” or “the juice.” It’s how books make money regardless of outcome, and it’s exactly why blindly betting favorites (or underdogs) without any edge loses money over the long run.

Moneyline vs spread vs total — three different bets, same odds format

American odds show up on all three major bet types:

• Moneyline: a straight bet on who wins the game outright.
• Point spread: a bet on the margin of victory, with odds (usually close to -110 on each side) attached to whichever side of the spread you take.
• Total (over/under): a bet on the combined score of both teams, again typically priced near -110.

That recurring -110 you’ll see everywhere is the sportsbook’s standard vig on close-to-even bets — you’re risking $110 to win $100, which means you need to win more than 52.4% of these bets just to break even.

Why tracking your bets in units — not dollars — matters

Serious bettors don’t talk in dollars; they talk in units, where one unit equals a fixed percentage of their bankroll (commonly 1–2%). This keeps performance comparable regardless of stake size and is exactly how PICK VIZ tracks every pick automatically — win rate, net units, and ROI, computed the same way whether a capper is betting $10 or $10,000 a game.

The takeaway

American odds aren’t actually complicated — they’re just unfamiliar. Once you can convert a line to implied probability in your head, you can start asking the only question that matters: does this price actually reflect the real chance of this outcome, or is there value here? That question is the entire foundation of profitable sports betting, and it’s a lot easier to answer when your picks, odds, and results are tracked automatically instead of scratched out on a notepad.