Polymarket
On-chain prediction markets for real-world information
CLOB + AMM hybrid Binary outcomes Conditional tokens (?U) $POLY governance
? What is Polymarket?
Polymarket is an on-chain prediction market platform where people trade on the outcomes of real-world events. Unlike traditional betting platforms, it's decentralized and permissionless - anyone can create a market on any resolvable question, and anyone can trade on it. Markets are structured as binary outcomes: YES or NO. If your prediction is correct, your share settles at $1.00. If not, it settles at $0.00.
What makes Polymarket architecturally interesting is its CLOB-AMM hybrid: a central limit order book for professional market makers, backed by an automated market maker that guarantees liquidity for any trade. The AMM layer also uses conditional tokens (?U) - outcome tokens that can be split and recombined - making the system composable and enabling the dispute resolution mechanism.
Market Lifecycle
Every market progresses through four phases. Tap each stage to learn what happens.
Binary Market Pricing - How the AMM Moves Price
The AMM prices YES shares at P(YES) = Q_yes / (Q_yes + Q_no). When traders buy more YES shares, Q_yes rises and the price moves up. Drag the slider to see how demand shifts the probability and what you pay per share.
Pay $0.75 -> if YES wins -> receive $1.00
Net profit: +$0.33 per share
Pay $0.25 -> if YES wins -> receive $1.00
Net profit: +$0.75 per share (3:1 odds)
? Share Pricing Calculator
See what your position is worth before and after market resolution. The payout depends on where you think the true probability lies vs. what the market says.
CLOB + AMM Flow: How Orders Get Matched
Polymarket uses a hybrid CLOB-AMM architecture. When you place a trade, the system checks the order book first. If there's a matching counterparty at your price, your order fills against the CLOB at that price. If not, it fills against the AMM at the current market price.
You submit a buy order for YES at $0.65. The order goes to the matching engine.
Matching engine looks for existing limit orders at $0.65 or better. If a market maker posted a sell order at $0.64, your order fills there - better price!
If the order doesn't cross the spread on CLOB, it trades against the AMM at the current price. The AMM always has liquidity - it's the backstop. This also moves the AMM price.
The matching result is written to the Polygon blockchain. ?U conditional tokens are minted/burned. Settlement is guaranteed by the AMM invariant.
Markets & Resolution
CLOB market-making, binary question design, market maker hedging, resolution mechanics, and the ?U dispute process.
Betting Mechanics
Conditional token AMM, effective cost formula, share purchase simulator, fees, and how Polymarket differs from Betfair.
AMM Pricing
Constant-product invariant, AMM rebalancing, slippage, arbitrage, and price convergence across prediction markets.
Liquidity Provider Mechanics
Market makers provide liquidity to Polymarket by depositing outcome tokens into the AMM. They earn a spread on every trade that fills against them, and they can also receive governance emissions if the market is in an incentivized pool.
LP risk: Liquidity providers are exposed to the outcome of the market. If a 60%-probability market resolves YES, the NO tokens (40M) are worthless and the LP loses $16M. The LP's position is not delta-neutral unless they actively hedge by also holding YES tokens in the right proportion - a full LP position carries directional risk equivalent to the AMM probability.
Key concepts
- Binary outcome markets
- Every Polymarket market resolves to exactly one of two outcomes: YES or NO. Shares in the winning outcome settle at $1.00; shares in the losing outcome settle at $0.00. There are no multi-outcome markets and no partial payouts - it's a clean binary instrument, which makes pricing straightforward and settlement unambiguous.
- CLOB-AMM hybrid
- Polymarket's matching engine runs on-chain and supports both limit orders (the CLOB layer) and AMM fills. Market makers post limit orders to the order book; if there's no match, the trader fills against the AMM. The AMM always provides a guaranteed bid and ask, which means no market is ever completely illiquid - even thinly traded markets have AMM-backed prices. The spread between CLOB best bid/ask and AMM mid is typically 0.5-2%.
- Conditional tokens (?U)
- A conditional token framework where each outcome token can only be redeemed if its condition is met. When you deposit collateral (say, USDC) into a binary market, the protocol mints equal quantities of YES tokens and NO tokens. Each set is worth at most $1 in aggregate - after resolution, the winning tokens are worth $1 and the losing tokens are worth $0. This construction is what makes markets composable, enables the dispute resolution mechanism, and lets traders reason about positions as probability-weighted claims.
- AMM pricing invariant
- The AMM uses a constant-product construction: P(YES) = Q_yes / (Q_yes + Q_no). When a trader buys YES, Q_yes increases and the price rises. When a trader buys NO, Q_no increases and the YES price falls. The invariant ensures the AMM is always producing a valid probability distribution (prices sum to 1.0). The AMM price is a real-time crowd-sourced probability estimate - it's not set by an oracle, it's emergent from trading activity.
- Market creation and seeding
- Anyone can create a market by posting the question, setting a resolution date, and seeding initial liquidity. The creator provides liquidity (typically $100-$500 equivalent) which gets deposited into the AMM, providing the initial trading depth. Creator fees are zero - the protocol earns on trading spreads and fees, not on market creation. Markets that don't attract enough trading volume can become illiquid and difficult to trade.
- Oracle resolution and disputes
- When an event concludes, an oracle reports the outcome to the contract. There is a dispute window where any holder of the relevant ?U tokens can challenge the report by posting a bond. If the dispute succeeds, the oracle is slashed and the correct outcome is used. This mechanism makes false oracle reports economically costly and creates a financial incentive for token holders to vote correctly. The ?U tokens themselves serve as the "jury" - their holders have skin in the game and are financially motivated to report honestly.
- POLY governance token
- POLY is the native governance token of the Polygon DAO which governs Polymarket. Token holders vote on protocol upgrades, fee parameters, oracle selection, market rules, and community treasury allocations. POLY is also used for oracle staking - oracles must stake POLY to report outcomes, and bad actors can be slashed. POLY is not required to trade - anyone can trade on Polymarket without holding POLY, which keeps the market accessible.
Why Polymarket matters
Polymarket became the dominant venue for on-chain prediction markets by combining the accessibility of a modern web interface with the trust guarantees of a decentralized settlement layer. Its CLOB-AMM hybrid is architecturally interesting - it solves the liquidity chicken-and-egg problem that plagued earlier prediction markets (like Augur) by always guaranteeing an AMM backstop, while still delivering CLOB-quality spreads for professional traders. The conditional token framework makes the system composable and enables the on-chain dispute resolution that gives participants confidence that outcomes will be correctly settled.
The platform's success also reflects a broader trend: information markets are a legitimate use case for blockchain technology. When a market on "Will the Fed cut rates by March 2026?" has $50M in volume and a clear price, that price is arguably a better prediction tool than any individual analyst. Polymarket's growth to over $3.4B in cumulative volume by 2026 demonstrates that there's real demand for credible, permissionless information markets - and the AMM pricing mechanism produces genuine probabilistic signal rather than just speculation.
Frequently asked questions
- What makes Polymarket different from a normal prediction market?
- Polymarket runs on a CLOB-AMM hybrid instead of a pure automated market maker. The order-matching engine sits on-chain while liquidity is aggregated from market makers who post bids and asks. This means tighter spreads than a pure AMM, but the AMM still provides a guaranteed liquidity layer for any position - if your limit order doesn't fill, you can always trade against the AMM at the current price. The combination is unique to Polymarket in the on-chain prediction market space.
- How does the AMM price actually get set?
- The AMM uses a variant of the constant-product invariant. For a binary YES/NO market, the AMM prices each outcome as P = Q_yes / (Q_yes + Q_no), where Q_yes and Q_no are the outcome token quantities. When you buy YES shares, you burn YES outcome tokens and mint NO tokens (and vice versa), which shifts the ratio and moves the price. The AMM always prices between $0 and $1, and the price reflects the crowd's probability estimate. This is the same invariant used by conditional token frameworks - UMA, Reality Keys, and several other on-chain prediction systems.
- What are ?U (conditional tokens) and why do they matter?
- Conditional tokens (often rendered as ?U or just CT) are a primitive that lets you split a single deposited asset into outcome tokens. For example, if you deposit $100 into a binary market about 'Will it rain on Jan 1?', you receive $100 worth of YES tokens and $100 worth of NO tokens. Each token settles at $1 if its outcome wins, and $0 if it loses - so one set is always worth $1 and the other is worth $0 after resolution. This construction makes markets composable and lets you trade individual outcome probabilities without building a separate smart contract for every market.
- Who can create a market and what are the requirements?
- Anyone can create a market on Polymarket, provided it meets minimum liquidity and wording standards. The creator must seed the market with enough liquidity to allow trading (typically $100-$500 equivalent in the asset). The question must be binary (yes/no), ambiguously worded markets get rejected by the oracle or community flagging. Markets must have a clearly resolvable outcome and a defined end date. Creator fees are 0% - the protocol earns on spreads and trading fees, not on market creation.
- How does a market resolve and how are disputes handled?
- Polymarket uses an oracle system (originally Gnosis Oracle, now internal or third-party oracles depending on market type) to determine the correct outcome. After the event date, an oracle reports the result. If traders disagree with the result, they can dispute within a window - the protocol runs a resolution vote using the conditional token holders as the jury. The bond system means false reports are expensive for the oracle. This is where the ?U mechanism comes in: dispute resolution happens through the conditional token holders (who have financial incentive to vote correctly), and the resolution propagates to settle all positions.
- What is the POLY governance token used for?
- POLY is the governance token of the Polygon DAO which governs the Polymarket protocol. Token holders vote on protocol upgrades, oracle selection, fee parameters, and market creation rules. The token also provides a security function: to report outcomes, oracles must stake POLY, and bad actors can be slashed. POLY holders also control a community treasury that funds protocol development, market creator subsidies, and liquidity incentive programs. POLY is not needed to trade - trading fees and market resolution are not token-gated.
- What are the main risks of trading on Polymarket?
- Five risks dominate. Oracle risk: the outcome report can be wrong or delayed, and disputes take time to resolve. Market manipulation: markets with low liquidity can be moved by large traders, especially near resolution. Illiquid spread risk: bid-ask spreads on long-tail markets can be 5-15%, making small trades expensive. Resolution timing: some markets take weeks to resolve after the event, locking capital. Regulatory risk: prediction markets exist in a gray area in some jurisdictions, and Polymarket has faced CFTC scrutiny - though as of April 2026 it continues to operate. Always treat position sizing in prediction markets as binary bets with real tail risk.
- How does Polymarket's CLOB-AMM hybrid compare to a pure CLOB like a traditional exchange?
- A pure CLOB (central limit order book) like NASDAQ or Binance matches limit orders from buyers and sellers at various price levels. Polymarket's hybrid adds an AMM as a backstop: if your limit order sits unmatched at $0.45 and the AMM is at $0.52, your order will never fill at your price - you can instead immediately trade against the AMM at $0.52. The AMM also provides the initial liquidity for new markets before professional market makers step in. The spread between bid and AMM-ask is typically tighter than pure-AMM designs (like those used by early Augur), which is why Polymarket's effective liquidity feels deeper than raw TVL suggests.