What Is a Binary Market? Yes/No Prediction Trading Explained

Definition

A binary market is a prediction market with two mutually exclusive sides, usually Yes and No. At ordinary resolution, the winning side has a settlement value of 1 and the losing side has a value of 0.

Binary markets are the simplest and most common type of prediction market. Examples include:

• “Will BTC close above $95,000 today?” (YES/NO)
• “Will the Fed cut rates in March?” (YES/NO)
• “Will it snow in London on Christmas Day?” (YES/NO)

Price Is a Probability Signal

If Yes trades at 0.65, traders often read that price as roughly a 65% market-implied probability. It is not a scientific forecast or a guaranteed execution price. It reflects the information, inventory, risk tolerance, fees, and liquidity represented in the current order book.

A complete Yes/No set has a combined gross settlement value of 1. Before resolution, however, the executable bids and asks available at a chosen size need not add to exactly 1.0. Spread and limited depth can make buying Yes and buying No cost more than 1 in total, while the best bids can sum to less than 1.

That distinction matters when comparing markets. A displayed midpoint is useful for orientation, but a trader should inspect the actual prices and quantities available before treating it as a probability.

Payout and Risk

• Buy Yes at 0.40 and Yes wins — the gross settlement value is 1, so the gain before fees is 0.60 per share.
• Buy No at 0.25 and No wins — the gross settlement value is 1, so the gain before fees is 0.75 per share.

For an outright purchased outcome share, the maximum ordinary loss is the purchase cost. That bounded payoff does not remove spread, slippage, specification, liquidity, operational, or protocol risk. A trader can be directionally right and still make a poor trade by paying too much or misreading the resolution rules.

Binary Markets on Purrdict

Purrdict displays curated HIP-4 outcome markets on Hyperliquid mainnet and a separate permissionless testnet catalog. The interface shows both sides, order-book depth, expiry, and settlement status so users can evaluate the contract rather than relying on the headline alone.

Read how HIP-4 prediction markets work or open the live Purrdict market interface.