> ## Documentation Index
> Fetch the complete documentation index at: https://docs.outcome.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Outcome tokens and pricing: mint, burn, probabilities

> How outcome token prices stay coherent: mint and burn complete sets for 1 USDC, why prices sum to 1, and how to read each price as implied probability.

# Outcome tokens and pricing

This page explains the mechanics behind outcome tokens: where they come from, why their prices always sum to 100 cents (which equals 1 USDC), and what those prices represent.

### Outcome tokens

Every outcome on Outcome has two tokens: YES and NO (or UP and DOWN for directional markets). Each token has a single defining property: it pays 1 USDC at settlement if its side resolves, and 0 otherwise. That's the entire payoff structure. The price you pay for the token before settlement is what determines your gain or loss.

In a multi-outcome market, each individual outcome has its own YES and NO pair. Holding YES on an outcome means you're positioned for that outcome to resolve; the YES prices across all outcomes of the market are what sum to approximately 100 cents.

### Splitting and merging

The reason a YES and NO pair always sums to 1 USDC is a pair of protocol operations called splitting and merging.

**Splitting.** 1 USDC can be split into one YES and one NO token of the same outcome. Because exactly one of the two will pay 1 USDC at settlement, the pair is always worth 1 USDC.

**Merging.** A YES and NO pair of the same outcome can be merged back into 1 USDC. This is the reverse of splitting.

Most users never split or merge directly. They buy and sell tokens on the order book, and the protocol's merged book handles the equivalence automatically (buying YES at 40 cents is the same trade as selling NO at 60 cents). But split and merge are what anchor the pair to 1 USDC: if YES + NO ever drifted meaningfully away from 100 cents, traders could split or merge to capture the difference, which keeps prices coherent.

In multi-outcome markets, the outcomes of the same question are linked by additional protocol operations, so positions across outcomes stay consistent. One practical consequence: holding NO tokens across different outcomes of the same question is equivalent to a redeemable combination, and the protocol lets you redeem the corresponding USDC before the market settles.

### Why prices sum to 1

Because a YES and NO pair always merges back to 1 USDC, YES + NO ≈ 100 cents for every outcome at any time.

For a multi-outcome market, exactly one outcome resolves YES, so a set containing the YES token of every outcome pays exactly 1 USDC at settlement. That anchors the sum of YES prices across the market to approximately 100 cents.

The word "approximately" matters. In practice, prices sum to slightly less than 100 cents because of the spread (there's always a gap between the best bid and best ask on each side). But the bound is tight enough that the probability interpretation works.

### Prices as probabilities

Because the prices sum to approximately 100 cents, each price can be read as the market's implied probability for that specific outcome.

A YES at 40 cents means the market is collectively pricing the event at 40% likely. A NO at 60 cents means the market is pricing the event at 60% likely *not* to happen. They sum to 100 cents, which corresponds to 100% probability that something happens.

In a multi-outcome market, the same applies. If candidate A trades at 50 cents, candidate B at 30 cents, and candidate C at 20 cents, the market is pricing A at 50% likely, B at 30%, and C at 20%. The three sum to 100%.

This is what makes prediction markets useful as a forecasting tool, even for people who don't trade. The prices aggregate the views of everyone buying and selling, producing a probability estimate based on collective belief and money at stake.