Beginner guide

Betting 101

A practical guide to guide to many of the terms used throughout this site and in the sports gambling world

Odds

Odds describe the tradeoff between risk and reward. Most commonly you will see odds in American format, decimal format, or in terms of implied probability.

American odds

American odds use + and - signs. A line like +150 means a $100 stake wins $150 in profit. In fact all underdogs will have odds greater than +100, with +100 indicating a fair bet. Meanwhile, a line like -110 means risking $110 to win $100 profit.

Decimal odds

Decimal odds show your total return per $1 staked. For example, 2.50 means a $1 bet returns $2.50 total if it wins. As such, decimal odds are always greater than 1.00.

Implied probability

Odds can be converted into a percentage called implied probability. This is the suggested chance suggested by the price before then accounting for any sportsbook margins or fees if applicable. A line that implies 55% is saying the outcome needs to happen a little more than half the time to justify the price.

Stake and Payout

The stake is the amount you put at risk. If you bet $10, your stake is $10. If the bet loses, you lose the stake. If the bet wins, your profit depends on the odds. Payout refers to what is paid out to you in a winning wager including your original stake.

Market Types

A market is the specific question you are betting on. The same game can offer several markets, and each one prices risk a little differently.

Moneyline

You pick the winner outright. There is no spread to cover, just a straight bet on which side wins.

Spread

You are betting on margin of victory. The favorite must win by more than the spread, or the underdog must keep the final margin within the number.

Total

You are betting on whether something goes over or under a number. This is often the game total, but it can also apply to player props like points, rebounds, or hits.

Yes/No

You are betting on whether a specific event will happen. These are common in prop markets and prediction markets.

Parlays

A parlay is one bet made up of multiple legs. Every leg must win for the parlay to win, so the payout is larger than a straight bet but the risk is also higher.

Parlays are popular because they create large payouts from small stakes (a same game parlay is when two of the legs are part of the same game). They are also dangerous because the book's edge compounds across legs, and one bad leg can sink the whole ticket. Many times a sportsbook may offer a 33% profit boost on a 3+ leg parlay, but beware this is not the profit opportunity it appears to be as perfect hedging will typically still lead to a net loss.

Vig

Vig, short for vigorish, is the sportsbook's built-in margin. It is the reason two opposite sides of a market usually add up to more than 100% implied probability.

A standard two-sided market at -110/ -110 is the classic example. Both sides look close to 50%, but the bettor must risk $110 to win $100. That spread is how the book makes money over time.

Contracts and Yes/No Markets

Exchange-style markets, including platforms like Kalshi or Polymarket, operate via tranding binary contracts directly against each other using an open order book. Prices fluctuate purely based on organic supply and demand. Instead of taking a posted sportsbook line, you are buying or selling binarycontract that resolves to Yes or No.

These contracts are usually quoted in cents. A contract trading at 63¢ is roughly saying the market prices the outcome near 63%. If it resolves yes, it pays $1. If it resolves no, it pays $0.

Important distinction

A sportsbook wager and an exchange contract can look similar, but they may not settle the same way if an event is delayed, canceled, postponed, or otherwise handled by special rules.

Pushes and Voids

Push

A push happens when the result lands exactly on the number you bet. If you bet over 7.5, there is no push. If you bet over 7 and the final total is exactly 7, the bet pushes and your stake is returned. Even though the original stake is returned, any promotion used on this wager is generally lost. Since ties happen so often in soccer, there are 3-way moneylines ensuring a push never occurs. However, there are a number of leagues where ties occur rarely (less than 5%) and thus sportsbooks maintain 2-way moneylines and on occasion push bets. Some of these leagues include the UFC, Japan's NPB, and Korea's KBO.

Void/Cancellations

A void means the bet is canceled and treated as if it never happened. Your stake is returned and typically so is any promotion you may have used on this wager. A void is different from a push because the event or market itself failed to settle under the book's rules, likely stemming from it never taking place. For example, if you wager that Player A will win a tennis match but Player B injures himself before the match even begins and drops out, this wager would be voided. If Player B injured themselves on the first point of the match and then drops out,

Why this matters for promos

Promotions may treat pushes and voids differently, especially across on platforms. Additionally, a bonus bet on a sportsbooks may be treated differently in these scenarios than a first-bet insurance promotion or a profit boost. For this reason it always important to reasearch the platforms you are betting on carefully. It is generally true that a voided bet returns a promotion unused. The same is not always true for a pushed bet which is why a conservative approach would avoid using pushable markets when employing valuable promotions. Below, I discuss sportsbooks with promotions involving bonus bets or no-sweat wagers where explicit terms go against this general practice, or we have confirmation that a pushed bonus bet consumes the promotion. To be clear most sportsbooks do not clearly state what happens to a promotion in a pushed market, not that that do not return the promotion in these cases.

FanDuel returns voided bonus bets but will not for pushed ones
DraftKings returns bonus bets for both pushed and voided wagers
BetMGM returns bonus bets for both pushed and voided wagers. It is not explicitly said anywhere though that a first-bet insurance promo is retained if that wager is pushed
theScore returns bonus bets for both pushed and voided wagers. It is not explicitly said anywhere though that a first-bet insurance promo is retained if that wager is pushed
Bet365 returns voided bonus bets but will not for pushed ones. In terms of the first-bet insurance promo, it appears to be closed in the event of a push or void
Prime Sportsbook explicitly returns bonus bets for voids but will not for pushes
Exchanges like Kalshi and Polymarket differ materially from traditional sportsbook settlement. In fact, they typically treat a voided market and a pushed market in the same manner. Polymarket will settle contacts 50/50 which means each contract which is for $1 will split its payout to both sides of the yes/no market. Hence, if you bought your contract for a favorite you will lose some money. and if you bought them as an underdog you will make a little money. For this reason, do not be afraid of hedging a market on Polymarket where the hedge is the underdog but be wary if you are betting on the favorite. On Kalshi, the wager will resolve at a stated fair market price rather than being voiding. This line of thinking gives Kalshi a lot of leeway and thus should make a better wary of wagering on a push possible market on Kalshi.

Maker and Taker

On exchange markets, you can either take an existing price or post your own order. If you accept someone else's open offer immediately, you are a taker. If you place an order that waits for someone else to accept it, you are a maker.

Makers add liquidity. Takers remove liquidity. Many exchanges treat those two actions differently when determining fees. Kalshi charges lower fees for makers while Polymarket actually rewards makers.

Liquidity

Liquidity is how much money is available at a given price. A market with strong liquidity has meaningful size near the best prices, so you can enter or exit without moving the market much.

As bet sizes increases, you may consume as a taker the best open orders and move onto worse prices. That means a small bet may receive the displayed price, while a larger bet may receive a worse average fill.

How to read odds scraper prices

Exchange prices shown on the Odds pages should generally be read as taker-facing prices. They reflect available open orders, not necessarily the better price you might get by posting a passive limit order and waiting.

Arbitrage

Arbitrage means placing bets on all relevant outcomes in a way that locks in a profit regardless of the result. In sports betting, this happens when different books or exchanges disagree enough that the combined prices create a guaranteed edge.

The point is not to predict the winner. The point is to exploit a pricing gap. True arbitrage is rare, often small, and can disappear quickly once books or market makers adjust.

Hedging

Hedging means placing another bet or trade that reduces the risk of an existing position. The hedge may lock in profit, reduce downside, or convert a promotion into a more predictable return.

Simple idea

If you have a bet on Team A, a hedge is a position on Team B or the opposite outcome that protects you if Team A loses. The best hedge is not always the one with the biggest payout; it is the one that fits the objective of the strategy. Much of this site is focused on hedging in a manner that maximizes the worst possible outcome -- this effectively means equalizing the payouts for every outcome.

Friend Referral

On many platforms, using a friend referral benefits both the referrer and the referee with some sort of promotion like bonus bets or profit boosts.
On some platforms, only the referrer receives the benefit. So, while it may not benefit your specific account, you can help a "friend" out.
On some platforms, using a friend referral can replace the normal new-user promotion that would otherwise be available. If the friend referral is less valuable than the normal new-user promotion, be sure to not use one.
Read the specific sportsbook strategy descriptions on this site in the Map tab for advice on how to best attack each new-user promotion and friend referral during registration.
Some friend referrals require entering a promo code during signup. Others require signing up through a referral URL link as opposed to signing up an app.

Promos

Sportsbook promotions generate value by artificially enhancing the expected return of a wager. While the vig built into betting markets normally causes fully hedged positions to lock in a small loss, promotions can more than offset this cost, allowing bettors to convert otherwise negative-return wagers into profitable ones.

Read the Strategy page for deeper promo walkthroughs and examples.