A prediction market is a marketplace where people buy and sell contracts tied to the outcome of a future event, and the price of each contract reflects the crowd's collective estimate of how likely that outcome is. If a contract pays out $1 when an event happens and $0 when it doesn't, then a price of $0.65 is the market saying there's roughly a 65% chance it happens.

That single idea, price equals probability, is what separates a prediction market from a poll, a pundit, or a sportsbook. Instead of asking people what they think for free, a prediction market asks them to back their opinion with money. The aggregate price that emerges is a real-time, numerical forecast that updates the moment new information arrives.

This guide explains what prediction markets are, how the mechanics work, why they tend to be accurate, how they differ from ordinary betting, and where you can actually use one.

How Do Prediction Markets Work?

Every prediction market is built around a clearly defined question with a verifiable answer, such as "Will candidate X win the election?" or "Will Bitcoin close above $100,000 on December 31?" The question must have an unambiguous resolution, because once the event concludes, the market needs to settle.

For each question, the market issues contracts on the possible outcomes, most often a simple YES and a NO. These contracts trade against each other on an order book or an automated market maker, exactly like shares trade on an exchange. You can buy when you think an outcome is underpriced and sell before resolution if the price moves your way.

When the event finally resolves, contracts settle on their true value:

• A correct outcome contract settles at $1.
• An incorrect outcome contract settles at $0.

The settlement itself is determined by a resolution source, sometimes called an oracle: a pre-agreed authority or data feed that reports what actually happened. On crypto-based venues this is handled on-chain; on regulated venues it is handled by the exchange. Either way, the rules for how a market resolves are published before you trade, so you always know what you are buying.

Price Equals Probability: A Worked Example

The price of a contract is the part newcomers most often misread, so it's worth slowing down.

Suppose a market asks, "Will it rain in London tomorrow?" YES contracts are trading at $0.40.

• The market is implying a 40% chance of rain.
• If you buy one YES contract for $0.40 and it rains, your contract settles at $1.00, a gross profit of $0.60.
• If it doesn't rain, your contract settles at $0.00 and you lose your $0.40 stake.

Notice that the payout is not arbitrary. A 40-cent price on a fair market means the expected value of the bet is roughly break-even: a 40% chance of winning $1 is worth about 40 cents. You make money only when you believe the true probability is higher than the price implies, and you turn out to be right.

YES and NO prices in a binary market sum to roughly $1, because exactly one of them will pay out. If YES is $0.40, NO is about $0.60. If you ever want to convert prices to percentages, just move the decimal: $0.40 is 40%, $0.72 is 72%. We cover this in more depth in how to read Polymarket odds.

Why Prediction Markets Work

Prediction markets are effective for two reinforcing reasons.

First, they aggregate dispersed information. No single forecaster knows everything, but thousands of participants each hold a small piece of the picture, an insider read on a campaign, a sharper weather model, a closer look at a company's earnings. The price pulls all of that scattered knowledge into one number.

Second, they impose skin in the game. A pundit who is wrong on television faces no cost. A trader who is wrong on a prediction market loses money. That financial incentive rewards accuracy and punishes wishful thinking, which is why prices tend to converge toward well-calibrated probabilities. Participants who are consistently wrong lose their capital and lose influence over the price; participants who are consistently right gain both.

This combination is why prediction markets have historically been competitive with, and in many cases ahead of, traditional polls and expert forecasts. They are not infallible, and thin markets can be noisy or manipulated, but the structural incentives push in the right direction. We examine the evidence and the limits in detail in how accurate is Polymarket.

Prediction Market vs Betting: What's the Difference?

People often assume a prediction market is just a rebranded sportsbook. The behaviors overlap, but the structure is fundamentally different.

The key distinctions are tradability and information. In a prediction market you can take a position and close it at any time, capturing a profit or cutting a loss as the price moves, just like trading a stock. And because the price is set by participants rather than a house margin, it functions as a genuine forecasting tool, not merely a wager. Politics and probability traders care about prediction markets precisely because the number on the screen means something. For a venue-specific breakdown of how this compares to the bookmaker model, see Polymarket vs sportsbooks.

Where to Use Prediction Markets

Prediction markets fall into two broad categories, and the right one for you depends largely on where you live.

Crypto / on-chain markets settle in stablecoins on a blockchain. They are open globally, run on smart contracts, and tend to list the widest range of questions. Polymarket, built on the Polygon network, is the largest by volume and is the venue most people mean when they talk about prediction markets today. If you're new, our guide to using Polymarket walks through the full flow.

Regulated exchange markets operate under financial oversight. In the United States, the CFTC-regulated exchange Kalshi offers prediction markets denominated in US dollars through a conventional brokerage-style account. The trade-off is a narrower, vetted catalog of markets in exchange for clear regulatory standing. We put the two head to head in Polymarket vs Kalshi.

Both categories share the same underlying mechanic, price equals probability, but differ in custody, settlement currency, and jurisdiction. Legality varies by country and, in the US, by state and venue, which is why we keep a dedicated, up-to-date explainer in is Polymarket legal in the US.

Beyond pure speculation, traders use these markets to hedge real-world exposure (a business worried about an election outcome can offset it), to track probabilities as a news instrument, and to trade for profit by spotting mispriced contracts.

How to Start Trading on a Prediction Market

Getting started is straightforward once you understand the mechanics. The exact steps depend on the venue, but the shape is the same everywhere.

1. Choose a venue: Decide between a crypto market like Polymarket or a regulated exchange like Kalshi, based on your jurisdiction and whether you want stablecoin or USD settlement.
2. Fund your account: On a crypto venue you deposit a stablecoin such as USDC; on a regulated exchange you fund a brokerage-style balance with dollars.
3. Find a market you understand: Read the resolution rules carefully. Knowing exactly how a market settles is the difference between an informed trade and a gamble.
4. Read the price as a probability: A contract at $0.30 implies a 30% chance. Buy only when you believe the true odds are better than the price.
5. Place your trade: Buy YES or NO, choose your stake, and confirm. Your maximum loss is the amount you put in.
6. Manage the position: You can hold to resolution or sell early if the price moves in your favor or you want to cut a loss.

If you'd rather learn from people who already do this well, you can study top performers on the trader leaderboard before risking your own capital.

Frequently Asked Questions

What is a prediction market?

A prediction market is a marketplace where people trade contracts tied to the outcome of a future event. The price of each contract, between $0 and $1, reflects the market's collective estimate of how likely that outcome is. When the event resolves, a correct contract pays out $1 and an incorrect one pays $0.

How do prediction markets work?

Each market poses a question with a verifiable answer and issues YES and NO contracts that trade against each other. The price moves with supply and demand as participants buy and sell, so it acts as a live probability estimate. When the event concludes, a resolution source determines the result and contracts settle at $1 or $0.

Are prediction markets accurate?

They are often more accurate than polls and pundits because they aggregate dispersed information and reward participants financially for being right. Accuracy improves with trading volume; thin or illiquid markets can be noisy. For a detailed look at the evidence and where it breaks down, see how accurate is Polymarket.

Are prediction markets legal?

It depends on your jurisdiction. Some venues operate under financial regulation, such as the CFTC-regulated exchange Kalshi in the United States, while crypto-based venues like Polymarket are restricted or unavailable in certain regions. Rules change frequently, so check our current breakdown in is Polymarket legal in the US.

What's the difference between a prediction market and betting?

In a prediction market the price is set by other traders, you can sell your position before the event resolves, and the price functions as a probability estimate. A traditional sportsbook sets odds with a built-in house margin, usually locks you in until the result, and profits when you lose. Prediction markets behave more like trading a stock than placing a wager.

Can you lose money in a prediction market?

Yes. Prediction markets are speculative trading, and if your contract resolves incorrectly you lose your entire stake on that position. There are no guaranteed returns. Trade only with money you can afford to lose, and make sure you understand each market's resolution rules before committing capital.

The Bottom Line

A prediction market turns a question about the future into a tradable price, and that price is the crowd's best estimate of probability. The mechanic is simple, the incentives are honest, and the result is a forecasting tool that has repeatedly outperformed traditional methods. Whether you use one to hedge, to read probabilities, or to trade for profit, the first skill to master is reading price as probability.

Once you're comfortable with the basics, the fastest way to improve is to learn from the people already winning. FrenFlow lets you track the sharpest traders and copy their trades automatically, so you can put these concepts to work without starting from zero.