Prediction Market Translator
Enter any share price to instantly see your real odds, exact payout, and platform fees — in plain English.
Worked Example (Illustrative Only)
These examples demonstrate how the formulas work using hypothetical assumptions.
The market: "Will the Fed cut rates at the next meeting?" You want to spend $100 on YES.
You're paying 63¢ per share for a contract that pays $1 if the Fed cuts rates. After Kalshi's $2.59 taker fee, your 158 shares would net you $55.41 in profit — a 55.4% return on your $100. If the Fed doesn't cut, you lose the full $100.
Prediction Markets Explained
New to prediction markets? These are the questions every beginner asks.
How do prediction market prices work?
On platforms like Kalshi and Polymarket, contracts trade between 1¢ and 99¢. The price represents the market's implied probability that an event will happen. A contract priced at 73¢ means the market thinks there's roughly a 73% chance the event occurs. If you buy YES at 73¢ and the event happens, you receive $1 per contract — a profit of 27¢ per share. If it doesn't happen, you lose your 73¢.
Why do YES and NO always add up to $1?
Every prediction market contract has two sides: YES and NO. If YES is priced at 73¢, NO is priced at 27¢. Together they always equal $1 because exactly one side must win. When the event resolves, the winning side pays out $1 and the losing side pays $0. This $1 structure is what makes the math clean — the price in cents directly equals the implied probability in percent.
What's the difference between Kalshi and Polymarket?
Both are prediction market platforms where you trade on real-world events, but they operate differently. Kalshi is a US-regulated exchange overseen by the CFTC — you trade in US dollars and it works like a traditional brokerage. Polymarket is a crypto-native platform where you trade with USDC stablecoins on the Polygon blockchain. Kalshi charges a formula-based transaction fee on every trade. Polymarket Global charges zero fees on most markets but has gas costs for deposits and withdrawals.
How does Kalshi make money if contracts only pay $1?
Kalshi charges a transaction fee every time your order fills. The fee is based on the contract price — it's highest at 50¢ (about 1.75¢ per contract) and lowest near 1¢ or 99¢. The formula is 0.07 × P × (1−P) per contract for taker orders, but the actual fee ranges from about 0.2% to 3.5% of your position size. Kalshi makes money on every trade regardless of whether the buyer wins or loses. There's no fee when your contract settles.
Can I sell my contracts before the event happens?
Yes. You don't have to hold a contract until it resolves. On both Kalshi and Polymarket, you can sell your position at any time at the current market price. If you bought YES at 40¢ and the price moves to 65¢, you can sell for a 25¢ profit per contract without waiting for the event to finish. This is similar to selling a stock — you lock in your gain (or cut your loss) early.
What happens if I buy NO instead of YES?
Buying NO is just betting the other direction. If YES is priced at 73¢, NO costs 27¢. If the event does NOT happen, your NO contract pays $1 — a profit of 73¢ per share. If the event does happen, you lose your 27¢. Buying NO at 27¢ is mathematically identical to selling YES at 73¢. The calculator above works for both sides — just enter the price you're paying.
How much money can I lose on a prediction market trade?
The maximum you can lose on any trade is the amount you spent buying the contracts. If you buy 100 contracts at 73¢ each, your maximum loss is $73. Prediction market contracts cannot go below $0, so unlike some financial products, you cannot lose more than your initial investment. There are no margin calls or leverage on standard Kalshi and Polymarket contracts.
Are prediction markets the same as sports betting?
They share similarities but are structurally different. In sports betting, you bet against a bookmaker who sets the odds and takes a margin. In prediction markets, you trade against other users at prices set by supply and demand — there's no "house" on the other side of your trade. Prediction markets also cover far more than sports: elections, weather, economics, crypto prices, Fed decisions, and cultural events. Kalshi is regulated by the CFTC as a derivatives exchange, not as a sportsbook.