The Bankroll Brief Starter Guide (free, 21+)

How to read a betting line, size a bet, and keep a budget you can live with

Bankroll Brief gives information and opinions only. We do not take bets and we do not guarantee results. Most people who bet lose money over time. Only bet what you can afford to lose.

1. Reading American odds

• Negative number (e.g. -110): how much you risk to win $100. At -110 you risk $110 to win $100.
• Positive number (e.g. +150): how much you win on a $100 bet. At +150 a $100 bet wins $150.
• Spread (e.g. Commanders +7.5): the underdog can lose by up to 7 points and the bet still wins.
• Total (e.g. 52.5): you bet whether the combined score goes over or under that number.

2. Turning odds into a probability

The price tells you how often the bet has to win just to break even.

• Negative odds: probability = odds ÷ (odds + 100), using the number without its minus sign. At -110: 110 ÷ 210 = 52.4%.
• Positive odds: probability = 100 ÷ (odds + 100). At +150: 100 ÷ 250 = 40%.

So a bet at -110 has to win more than 52.4% of the time to make money in the long run. That is harder than it sounds.

3. The house edge ("vig")

Add up the break-even percentages on both sides of a market. At -110 / -110 that is 52.4% + 52.4% = 104.8%. The extra 4.8% is the sportsbook's margin. Lower-margin prices mean you need to be right less often.

4. Units: size every bet the same way

• Decide on a betting budget that is money you could lose without it hurting your bills or your life. This is your bankroll.
• One "unit" is a small, fixed slice of it. Many bettors use 1% to 2%.
• Our picks are given in units (for example "1 unit" or "0.5 unit") so you can scale them to your own budget.
• Never raise your unit size to win back losses.

5. Line shopping

Different legal sportsbooks often post slightly different prices on the same game. Getting -105 instead of -115 lowers your break-even rate from 53.5% to 51.2%. Over many bets, that difference matters more than almost anything else you control.

6. Keep a record

Write down every bet: date, odds, units, result. We log every pick, including losses, and publish the full record at https://bankrollbrief.com/track-record. Yours should be honest too, even if only you see it.

7. Know when to stop

Warning signs include chasing losses, betting more than you planned, borrowing to bet, or hiding it from people close to you. Set deposit and time limits in your sportsbook account; licensed books are required to offer them in many states.

If you or someone you know has a gambling problem, call or text 1-800-MY-RESET (1-800-697-3738), the National Problem Gambling Helpline. NY: 877-8-HOPENY or text HOPENY (467369). MA: 1-800-327-5050. NJ: 1-800-GAMBLER. OH: 1-800-589-9966.

21+ only (or the legal age in your state). Bankroll Brief provides information and opinions only, does not accept bets, and does not guarantee winnings. You make your own decisions.