Sports Betting Basics
Sports betting is wagering money on the outcome of a sporting event. You pick what you think will happen, the sportsbook sets odds, and if you're right, you win money. If you're wrong, you lose what you bet.
How Odds Work
Odds tell you two things: who's favored and how much you'll win.
American Odds (Most Common in US)
Negative numbers (-): The favorite. Shows how much you need to bet to win $100.
- Lakers -150: bet $150 to win $100
Positive numbers (+): The underdog. Shows how much you win if you bet $100.
- Spurs +200: bet $100 to win $200
Decimal Odds (Common Internationally)
Your total payout (including your stake back) per dollar bet.
- 2.50 means if you bet $10, you get back $25 total ($10 stake + $15 profit)
Fractional Odds (Common in UK)
The ratio of profit to stake.
- 5/2 means you win $5 for every $2 you bet
You don't need to memorize all three formats, but know how to read American odds at minimum.
Common Bet Types
Moneyline
Pick who wins the game. That's it.
Example: Lakers -180 vs. Spurs +150
Bet Lakers: risk $180 to win $100 Bet Spurs: risk $100 to win $150
No spreads, no totals. Just pick the winner.
Point Spread
The favorite has to win by more than a certain number of points. The underdog can lose by less than that number (or win outright) and you still win your bet.
Example: Celtics -6.5 vs. Bulls +6.5
If the Celtics win 110-102 (8-point margin), Celtics bettors win. If the Celtics win 108-105 (3-point margin), Bulls bettors win.
The .5 prevents ties. Most spreads are offered at -110 odds on both sides.
Over/Under (Totals)
Bet on whether the combined score of both teams will be over or under a certain number.
Example: Total is 215.5
Final score: Lakers 115, Spurs 105 = 220 points (Over wins) Final score: Lakers 102, Spurs 98 = 200 points (Under wins)
Parlays
Combine multiple bets into one. All of them have to win for you to get paid, but the payout is much higher.
Example: 3-team parlay
- Lakers moneyline
- Celtics -5.5
- Over 218.5 in the Nuggets game
If all three hit, you win big. If even one loses, you lose the whole bet.
Parlays have bad expected value long-term, but they're fun and people like the big payout potential.
Prop Bets
Bets on specific events within a game.
Examples:
- LeBron James over 28.5 points
- First team to score
- Will there be overtime?
Props are fun but often have worse odds than standard bets. Sportsbooks know casual bettors love props.
The Vig (Juice)
Sportsbooks don't offer fair odds. They build in a commission called the vig (short for vigorish) or juice.
Example: A coin flip should be 50/50, which would be +100 on both sides (even money). But sportsbooks offer -110 on both sides.
At -110, you bet $110 to win $100. If you win, you get $210 total ($100 profit + your $110 back). If you lose, you lose $110.
If 100 people bet $110 on heads and 100 people bet $110 on tails, the book collects $22,000 total. They pay out $21,000 to the winners and keep $1,000.
That $1,000 is the vig.
To break even at -110, you need to win 52.4% of your bets, not 50%. That extra 2.4% is the house edge.
Starting a Bankroll
Your bankroll is the total amount of money you've set aside for betting. This should be money you can afford to lose.
Rule of thumb: Bet 1-3% of your bankroll per bet.
If you have $500:
- Bet $5-15 per game
- Never bet more than $25 (5%) even if you're really confident
This protects you from going broke during a bad streak. Even good bettors lose 45% of their bets. Variance is real.
Tracking Your Bets
Don't just bet and forget. Track everything:
- Date
- Sport/league
- Teams
- Bet type (moneyline, spread, over/under)
- Odds
- Amount bet
- Result
After 50-100 bets, you'll see patterns. Maybe you're good at NBA totals but bad at NFL spreads. Lean into what works.
Common Beginner Mistakes
Betting favorites because they're "locks." Favorites lose ~35-40% of the time. And even when they win, they don't always cover the spread.
Parlays for "easy money." Parlays are fun but terrible long-term bets. The odds are stacked against you mathematically.
Chasing losses. You lose $50, so you bet $100 on the next game to "get it back." This is how you blow up your bankroll.
Not shopping lines. If one book has Lakers -5 and another has Lakers -4.5, bet at -4.5. That half-point matters over time.
Betting with your heart. You're a Lakers fan, so you bet on them every game. This isn't a strategy—it's fandom. Bet objectively or don't bet at all.
Is Sports Betting Profitable?
For most people? No. The vig makes it hard to win long-term. You need to win 52.4% of -110 bets just to break even.
But it's possible. Professional bettors exist. They:
- Have models or systems to find edges
- Shop lines obsessively
- Manage their bankroll carefully
- Treat it like a job, not entertainment
If you're betting for fun, set a budget and accept that you'll probably lose over time. If you want to win long-term, you need to study, track everything, and be disciplined.