Key Points
- American odds show profit on a $100 bet (positive) or amount needed to win $100 (negative).
- Start with moneyline and spread bets. They are the simplest markets to understand.
- Implied probability converts odds to a win percentage. It is the most important concept in betting.
- Set a dedicated bankroll and never bet more than 2–5% on a single game.
- Line shopping across multiple sportsbooks is free money over the long run.
What is Sports Betting?
Sports betting is placing a wager on the outcome of a sporting event. If your prediction is correct, you win money based on the odds. If not, you lose your stake. In the US, sports betting is legal in 38+ states and growing rapidly since PASPA was overturned in 2018.
Understanding American Odds
Every bet has odds attached. In the US, odds are expressed in the American format:
Negative odds (e.g., -150): You are betting the favorite. You must bet $150 to win $100 in profit.
Positive odds (e.g., +130): You are betting the underdog. A $100 bet wins $130 in profit.
The number 100 is the anchor. Negative = how much to risk for $100 profit. Positive = how much you win on a $100 risk.
The Three Core Bet Types
1. Moneyline
Simply pick which team wins. No spread involved. Example: Chiefs -180 vs. Raiders +155. Bet $180 on Chiefs to win $100, or bet $100 on Raiders to win $155.
2. Point Spread
The spread levels the playing field. Example: Chiefs -6.5. The Chiefs must win by 7 or more for spread bettors to win. Both sides are usually priced at -110.
3. Over/Under (Total)
Bet whether the combined score of both teams will go over or under a set number. Example: Total 47.5. Over wins if both teams combine for 48+ points.
The Vig: How Sportsbooks Make Money
Notice how both sides of a spread are usually priced at -110 instead of even money (+100)? That extra 10 is the vig (also called juice or commission). Sportsbooks don't need to pick winners. They profit from the vig as long as they balance action on both sides.
This is why bettors who go 50/50 lose money over time. You need to win roughly 52.4% of your -110 bets just to break even.
Step-by-Step: Placing Your First Bet
- Choose a licensed sportsbook in your state (DraftKings, FanDuel, BetMGM are the largest)
- Create and verify your account: you'll need ID verification
- Deposit funds: start small, $50–$100 to learn
- Navigate to your sport and find the game you want
- Select your bet type: moneyline, spread, or total
- Enter your stake and confirm the payout
- Place the bet: it's locked in once confirmed
Setting Up Your Bankroll
Your bankroll is money set aside exclusively for betting. Golden rules:
- Only use money you can afford to lose entirely
- Bet 1–3% per game (never more than 5%)
- Track every bet in a spreadsheet
- Never chase losses
Common Beginner Mistakes
Betting too many games. More volume = more exposure to the vig. Be selective.
Ignoring implied probability. Convert every line to a percentage before betting. -110 implies 52.4%. Do you really believe the team wins more often than that?
Not shopping lines. Getting +155 instead of +140 on the same bet adds up enormously over hundreds of bets. Have accounts at 2–3 books.
Parlays as a strategy. Parlays are entertainment, not investment. The house edge compounds with every leg.
Your First 30 Days
Focus on one sport you know well. Bet small. Track everything. Evaluate your results after 50–100 bets, not 5. The variance in sports betting means small samples are meaningless. Your goal in month one is learning, not profits.