Polymarket vs Kalshi, compared
Polymarket and Kalshi are the two biggest prediction markets, where you can trade on the outcome of real-world events and the price of a contract reads directly as the market's implied probability. The core difference is structure: Polymarket is crypto-native, settles on-chain, and operates globally, while Kalshi is a US-regulated exchange overseen by the CFTC. Together they drove prediction-market volume past tens of billions of dollars. This guide explains how they work and differ, neutrally. It is educational, not betting or investment advice.
Prediction markets went from a niche idea to a market with combined volumes running into the tens of billions of dollars, with two names dominating the conversation: Polymarket and Kalshi. They do something subtle and interesting, turning questions about the future into tradable contracts whose prices reveal what a crowd of people betting real money believes. This guide explains how they work, how the two leaders differ, and the risks, written neutrally and focused on understanding rather than participation.
How a prediction market works
A prediction market takes a yes-or-no question about the future, an election, an economic figure, a sporting result, and turns it into a contract that settles at one dollar if the event happens and zero if it does not. Because of that structure, the contract's price between zero and one dollar reads directly as the market's estimate of the probability. A contract trading at forty cents means the market is pricing roughly a forty percent chance. As new information arrives and people trade, the price moves, so it behaves like a live, constantly updated probability set by everyone with money on the line.
That is the useful idea behind prediction markets: prices as probabilities, aggregating many people's views and incentives into a single number that often tracks real outcomes well. It is also why their prices became something people watch as a signal, the way they watch polls or forecasts, not necessarily to trade but to read what the market thinks. That distinction, watching versus participating, matters a lot for how most people relate to these venues.
What Polymarket is
Polymarket is the crypto-native prediction market. It runs on a blockchain, settles trades on-chain, and uses stablecoins for positions, which lets it operate globally and permissionlessly in the way crypto applications do. Its on-chain nature means its markets and prices are publicly visible and verifiable, and it became the venue most associated with the explosive growth of prediction markets, especially around high-profile events that drew enormous volume and attention.
The crypto-native model is Polymarket's strength and its complication. It gives global reach and transparency, but it also places Polymarket under the evolving, uneven crypto rules that vary by jurisdiction, so availability and legality differ by country. It is the example people point to when they describe prediction markets as a crypto phenomenon, even though the underlying idea is older than crypto.
What Kalshi is
Kalshi took the opposite path: regulation first. It is a US-based prediction market operating as a regulated exchange overseen by the Commodity Futures Trading Commission, the federal regulator for derivatives. That status lets it offer event contracts legally to US users within a regulated framework, something the crypto-native model does not straightforwardly do. It is centralized, runs in dollars through the traditional financial system, and emphasizes compliance and oversight.
The trade-off mirrors Polymarket's in reverse. Kalshi's regulated status gives it legitimacy and a clear legal footing in the US, but it operates within the boundaries that regulation sets, on what contracts it can list and who can access it. Where Polymarket is global and on-chain, Kalshi is US-focused and regulated. The two represent the two roads prediction markets can take, and both have grown substantially.
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Download for MacWatching the odds versus trading
Here is the distinction that matters most for most people. There is a world of difference between watching a prediction market's probability and trading on it. The price, the implied probability, is information, a read on what a money-backed crowd expects, and watching it requires nothing and risks nothing. Trading on it means putting capital at risk on an uncertain outcome, which is an entirely different activity with real potential for loss.
CoinNotch sits firmly on the watching side of that line. It can display a prediction market's current price, the implied probability, in your Mac menu bar as a read-only ticker, the same way it shows a coin price. It does not place trades, take positions, connect to either venue's account, or suggest a side. It shows the number, and every decision and action stays with you and the platform you choose. The full boundary is laid out in our prediction-markets display feature page.
The risks worth understanding
Prediction markets carry real risks for anyone who participates. Trading on an outcome can lose the entire stake, since a contract that settles at zero is worth nothing. Liquidity varies by market, so some contracts are thin and hard to exit. The regulatory picture is uneven and shifting, with access, legality, and available contracts differing by jurisdiction and changing over time. And the crypto-native model adds the usual on-chain risks on top, while the regulated model adds the constraints of operating inside a legal framework.
None of this is a judgment on prediction markets, which are a interesting mechanism for aggregating beliefs. It is the honest context: a powerful idea, prices as probabilities, wrapped in venues that carry real participation risk and rules that differ by country. For most people the valuable part is reading the probabilities as a signal, which is exactly what a display tool supports, rather than the trading, which is where the risk lives.
Following prediction-market prices
For people who follow prediction markets as a signal, keeping a key market's probability in view through the day is a way to watch sentiment shift in real time, the same impulse as watching a price. The number updates as the crowd revises its view, which can be informative around events that matter to you.
CoinNotch shows prices, including prediction-market probabilities where available, in your Mac menu bar as a read-only glance, never as a trading tool. See the prediction-markets display feature for exactly how that boundary works, and the stablecoins explainer, since Polymarket settles in stablecoins.