You know odds. You know spreads. Prediction markets are not sports betting. Here is what is different, which platforms map to your background, and what traps to expect.
You know odds. You know spreads. Prediction markets are not sports betting — here is what to expect.
Prediction Market
60 cents = 60% implied probability. No vig baked in.
Sportsbook
-150 American odds = ~60% implied probability, but with vig already included in the line.
Prediction Market
0–2% trading fee per trade, charged separately. Some platforms charge nothing at resolution.
Sportsbook
4–10% vig baked into every line. You never see it itemized — it is just built into the spread.
Prediction Market
Politics, economics, weather, entertainment, sports. Events with clear yes/no resolution criteria.
Sportsbook
Primarily sports and entertainment outcomes with point-spread structures.
Prediction Market
Contract wording defines resolution. Read the criteria before you place — same event can resolve differently on different platforms depending on exact wording.
Sportsbook
Sportsbook sets and interprets payout rules. You trust the house.
Prediction Market
CFTC-regulated prediction markets may be treated as Section 1256 derivatives (Form 1099-B, capital gains rates) — not gambling income. Verify with a tax professional.
Sportsbook
Sportsbook winnings are gambling income (Form W-2G for qualifying wins). Different from PM tax treatment.
Translate cents into a fee-adjusted sportsbook-style comparison before treating the visible price like a ticket.
Displayed market
60¢ YES
60.0% implied
Comparison fill
63¢ YES
Uses your worst acceptable fill
Fee-adjusted probability
64.6%
$102.59 cost on ~158.7 contracts
Sportsbook-style equivalent
-183
Comparison price, not an offered line
Fee input from Kalshi
≤1.75¢/contract (formula-based)
Uses Kalshi's probability-based entry-fee formula from platform fee data.
Estimated explicit entry fee: $2.59.
Sportsbook habit translation
Instead of clicking the visible line, choose the maximum price you are willing to accept, include explicit fees, then compare the fee-adjusted probability to your sportsbook-style number.
Displayed price is not necessarily your executable price. Your comparison uses the worst fill you said you would accept.
This calculator is an education aid for comparing cost stacks. It is not a sportsbook offer and it does not say whether a trade is good.
⚠️ Displayed price is not always executable price
A 60¢ market can become a 63¢ fill if you use a market order or if the book is thin. Set a limit price, compare the fee-adjusted fill, and read the resolution source before treating the number like sportsbook odds.
Run the full fee calculator →Contract type changes the risk question
Before treating a prediction-market price like a sportsbook line, label whether the contract is a team outcome, player-injury/non-participation outcome, first-play question, officiating trigger, broadcast trigger, or collateral/margin model.
Use the sports-contract risk labels →Try DraftKings Predictions or FanDuel Predicts — familiar UX, CFTC-regulated via CME Group. Your existing account may already have prediction markets enabled.
Try Robinhood Prediction Markets — zero friction, powered by Kalshi infrastructure.
Try Kalshi or Interactive Brokers ForecastEx — widest market selection, deepest order books.
Try Polymarket — crypto-native, USDC-based, US access via Polymarket US (QCX LLC) (CFTC-authorized). Best for geopolitical and global events.
⚠️ Near-Certainty Contracts Are Not Guarantees
A 98-cent YES contract feels like a -5000 moneyline. It is still a risk. Thin order books mean you may not fill at that price, and the implied 2% loss risk is real. Do not size them like sure things.
Why Near-Certainty Contracts Still Carry Risk →⚠️ Contract Wording IS the Line
The resolution criteria define what you are buying. The same real-world event can resolve YES on one platform and NO on another if the contract wording differs. Read before you place.
See Contract Settlement Comparison →⚠️ Taxes Are Different — Check Before Filing
PM winnings on CFTC-regulated platforms may be derivative income, not gambling income. This can be better or worse depending on your tax situation. Do not assume sportsbook rules apply.
Prediction Market Tax Guide →Full guide to Kalshi: markets, fees, and how to get started.
Why 98-cent contracts are not as safe as they look.
Classify forfeits, strikes, abandoned games, late postponements, and official corrections.
How prediction market winnings are taxed vs sportsbook winnings.
Compare all prediction market platforms side by side.
The legal and regulatory answer.
Find out if prediction markets are available in your state.
