Understand sports betting and prediction markets from the inside
How odds are priced, where the margin hides, how parlays and cash out really work, and how prediction markets compare. Clear guides plus interactive tools you can try yourself.
Odds converter
Type any odds to see the implied probability.
Learn the fundamentals
Start with the basics or jump straight into how sportsbooks actually build their prices.
Sports Betting Basics
Moneylines, spreads, totals and props explained without jargon.
- How to read odds
- Bet types explained
- Bankroll basics
Prediction Markets Explained
How event contracts work, why price equals probability, and how you trade them.
- What is an event contract
- Buying and selling Yes / No
- Fees and liquidity
Odds & Probability
Implied probability, the vig, and how to find fair odds behind any price.
- What is vig / juice
- No-vig fair odds
- Expected value
Parlays & Same Game Parlays
How parlay odds are calculated and why correlated legs are priced differently.
- Parlay math
- SGP correlation
- Buying points
Cash Out
How a sportsbook calculates your cash out offer and when taking it makes sense.
- The cash out formula
- Partial cash out
- Live vs pre-match
Live Betting
Why live odds move, suspensions, delays and how in-play markets are traded.
- Odds movement
- Market suspensions
- Live strategy basics
Sportsbook vs prediction market
Both let you take a position on an outcome. The way prices are set, and who you are trading against, is very different.
| Sportsbook | Prediction market | |
|---|---|---|
| Who sets the price | The bookmaker's trading team and models | Buyers and sellers on an exchange |
| Who you play against | The house | Other traders |
| How the platform earns | Margin built into the odds (vig) | Trading or settlement fees |
| Price format | American, decimal or fractional odds | Contract price, e.g. 62¢ = 62% chance |
| Exit before the result | Cash out, if offered | Sell your contract any time there is liquidity |
| Limits on winners | Can limit sharp accounts | Generally no limits by design |
| Markets | Sports, deep prop and live coverage | Sports, politics, economics, culture |
Free betting tools
Interactive calculators that show the math step by step, not just the answer.
Odds Converter
American, decimal, fractional and implied probability.
SoonParlay Calculator
Combined odds and payout for any number of legs.
SoonNo-Vig Calculator
Strip the margin and see the fair price.
SoonCash Out Estimator
See how a fair cash out value is calculated.
SoonExpected Value
Is this bet worth it at your estimated probability?
SoonArbitrage Calculator
Stake split across books or markets for a locked return.
SoonContract Price Converter
Prediction market price to sportsbook odds and back.
SoonHold Calculator
How much margin a market really carries.
Frequently asked questions
What is a prediction market?
A prediction market is an exchange where people buy and sell contracts on the outcome of an event. Each contract pays a fixed amount if the outcome happens, so its price reflects the market's estimated probability.
How is a prediction market different from a sportsbook?
A sportsbook sets the odds and takes the other side of your bet, building its margin (the vig) into the price. A prediction market matches traders against each other, and the platform usually earns through fees instead of setting the price.
What does implied probability mean?
Implied probability converts odds into the chance of an outcome the price suggests. For example, decimal odds of 2.00 or American odds of +100 imply a 50% probability.
Is sports betting legal where I live?
It depends on your country, and in the US on your state. Always check local regulations and only use licensed operators.
Get smarter about odds
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