What is a prediction market?

A prediction market is a regulated marketplace where traders buy and sell binary event contracts that pay $1.00 if the specified event resolves YES and $0.00 if it resolves NO. The current market price — expressed in cents between 0 and 100 — is the market's implied probability for that outcome.

How is a prediction market different from a sportsbook?

A sportsbook is a house that sets prices and takes the other side of every trade. A prediction market is an exchange where traders take both sides against each other. That structural difference means prediction markets generally have tighter spreads, no winner limits, and transparent price discovery rather than a bookmaker's margin baked into the odds.

Are prediction markets legal in the United States?

Kalshi is a CFTC-regulated Designated Contract Market and is legal for US residents in all 50 states. Polymarket is restricted for US residents under a 2022 CFTC settlement. DraftKings Predictions and FanDuel Predicts operate as licensed gaming products in a growing list of states. Availability depends on the platform and your location.

How do I make money on a prediction market?

You make money two ways. First, you can buy a contract at say 40¢ and hold it through resolution — if the event resolves YES, you collect $1.00 per share for a 60¢ profit. Second, you can trade out before resolution by selling to another trader at a higher price. Both depend on having a better probability estimate than the market consensus.

What tools do I need to start trading prediction markets?

At a minimum, you need a probability converter to translate prices into implied probabilities, an expected value calculator to identify mispriced contracts, and a bankroll-sizing framework like the Kelly Criterion. The free tools on PredictionMarketsPicks cover all three; the Pro suite adds an arb scanner and edge alerts for systematic traders.

How Prediction Markets Work: A Complete Guide for Traders (2026)

Prediction markets are event contracts that pay out based on whether a specific future event happens. They are not a new invention — academic research on them stretches back decades — but they are finally having their moment in the US under CFTC regulation, with Kalshi leading the way and DraftKings Predictions and FanDuel Predicts entering the space as well.

This guide breaks down how the mechanics actually work, what the prices mean, and the structural differences that make prediction markets different from sportsbooks, crypto casinos, or daily fantasy.

The binary contract

Every prediction market contract is a binary option. It pays exactly one of two amounts:

$1.00 if the event resolves YES
$0.00 if the event resolves NO

The price of the contract moves between 0¢ and 100¢ as traders buy and sell. That price is the market's implied probability for the YES outcome. A contract trading at 65¢ means the market thinks there is a 65% chance the event happens. A contract at 10¢ implies a 10% probability. That's it — no moneyline, no point spread, no vig baked in.

This is the single most important idea in prediction market trading. Every price you see is a probability. Once you internalize that, the rest of the mechanics fall into place. The Probability Converter can help translate between Kalshi cents, American odds, and decimal odds if you're coming from a sportsbook background.

Where the price comes from

Unlike a sportsbook, the price on a regulated prediction market is not set by a house. It is set by traders buying and selling against each other in an order book. If more traders are willing to buy at 65¢ than sell, the price rises. If more want to sell than buy, it falls.

On Kalshi, the order book is fully visible — you can see the bids and asks at every price level, and you can choose to take an existing offer or post a new one. On Polymarket, the structure is slightly different but the economics are the same: price is a function of supply and demand between traders, not a bookmaker's margin.

That structural difference matters. On a sportsbook, the house always wins over time because the vig is baked into every line. On a prediction market, the platform collects at most a small fee per trade (Kalshi is commission-free for most retail flow); the money flows between traders based on who was right.

Resolution and settlement

Every prediction market contract has a written resolution criterion. Before you trade, read it.

Examples of real resolution criteria:

"Will the Fed cut rates in June 2026?" — Resolves YES if the FOMC announces a target rate below the prior meeting's target at its June 2026 meeting.
"Will the Miami Heat win the 2026 NBA Finals?" — Resolves YES when the NBA officially awards the championship.
"Will the high temperature in Denver on April 18 exceed 72°F?" — Resolves YES based on the official NWS observation.

Resolution is mechanical and pre-specified. There is no subjective judgment, no sliding scale. Either the condition is met by the deadline or it is not. When resolution happens, winning contracts auto-settle at $1.00 and losing contracts at $0.00.

What makes a market mispriced

A prediction-market contract is mispriced when its price diverges from the true probability of the event. If the real probability of a Fed cut in June is 55% and the contract is trading at 42¢, you have a 13-point edge — the market is underpricing the event relative to the fair value.

Finding these gaps is the entire game. The usual sources:

1. Slow crowd reactions. News breaks; it takes hours or days for the full crowd to re-price. Sharp traders move first.

2. Structural biases. Retail traders over-weight recent outcomes and round numbers. Markets anchor on prices that feel right rather than prices that are right.

3. Cross-platform divergence. The same event often trades at different prices on Kalshi, Polymarket, and DraftKings Predictions. One of them is usually closer to fair.

4. Low-liquidity markets. Thinly traded contracts can sit at stale prices for extended periods because nobody has bothered to re-price them.

Once you spot a mispricing, the EV Calculator converts the gap into an expected-value percentage — the number that tells you whether the trade is worth the size and the risk.

How prediction markets compare to sportsbooks

Sportsbooks package the same underlying probability question inside a +150 moneyline or a -7.5 point spread. The vig is invisible, but it is always there — typically 4–5% on standard markets, 15%+ on parlays. Winners get their accounts limited; losers are welcomed.

Prediction markets price probabilities directly, have no winner limits (the platform doesn't care which side of a trade you are on), and post transparent order books. The tradeoff is fewer sports markets and a different risk profile — if you want to trade the Lakers -4.5, the prediction-market equivalent is a moneyline contract, not a spread.

For a deeper side-by-side, the Kalshi vs Polymarket comparison breaks down exchange structure, fees, state availability, and sports coverage across both platforms.

Getting started

A practical first session looks like this:

1. Open an account with a platform available in your state. Kalshi covers all 50 US states; DraftKings Predictions and FanDuel Predicts vary by state.

2. Read the resolution criteria for a few markets you find interesting. Train your eye for specificity.

3. Pick one market and build your own probability estimate before checking the price. Compare your estimate to the market; use the EV Calculator to see whether there is an edge.

4. If you decide to trade, size conservatively. Professional traders use quarter Kelly — the Kelly Criterion calculator produces the exact number.

5. Track everything. Outcome, entry price, reasoning. Patterns emerge over 30–50 trades that are invisible over 3.

Prediction markets reward calibrated thinking over hot takes. The structural math is clean; the edge is in how well you estimate probabilities and size positions. Everything else is noise.