Short answer
On a prediction market, a Yes share pays $1 if Yes wins, so its price is the market's probability: $0.40 means about 40%. Your payout if you win is your amount divided by the price, so $2 at $0.40 returns $5, a $3 profit. Decimal odds are $1 divided by the price, here 2.50. Yes and No prices usually add up to a bit more than $1 for buyers; that extra is the spread. A price is only worth paying if you believe the real chance is higher than the price.
Prediction markets do not show odds the way a bookmaker does. They show a price between 0 and 1. That price is the cleanest way to express a chance there is, and it makes the payout math almost trivial. This guide shows how to read it, how to convert it to any odds format, and how to think about whether a price is worth paying.
What does a prediction market price mean?
A share pays $1 if its side wins and $0 if it loses, so its price is the market's chance that it wins. $0.40 means about 40%, $0.75 means about 75%.
That is why people say price equals probability. If traders collectively think something happens 4 times out of 10, the fair price for a $1 ticket on it is 40 cents. On Hyperliquid's outcome markets, prices move between 0.001 and 0.999, which is 0.1% to 99.9% (>Chainstack developer guide). The share itself is explained in what are outcome tokens.
How do you turn a price into a payout?
Divide your amount by the price: that is your number of shares, and also what you get back if you win. Subtract your amount to get the profit.
| Price | Chance | $2 buys | You get back if you win | Profit if you win |
|---|---|---|---|---|
| $0.10 | 10% | 20 shares | $20 | $18 |
| $0.25 | 25% | 8 shares | $8 | $6 |
| $0.40 | 40% | 5 shares | $5 | $3 |
| $0.50 | 50% | 4 shares | $4 | $2 |
| $0.80 | 80% | 2.5 shares | $2.50 | $0.50 |
The pattern is always the same: the less likely the side, the bigger the payout. A low price is the market saying "probably not", not a discount.
How do prices compare with betting odds?
Decimal odds are $1 divided by the price. Fractional and American odds are other ways to write the same thing. A price of $0.40 is decimal 2.50, fractional 3/2, and American +150.
| Price | Decimal odds | Fractional | American |
|---|---|---|---|
| $0.25 | 4.00 | 3/1 | +300 |
| $0.40 | 2.50 | 3/2 | +150 |
| $0.50 | 2.00 | 1/1 | +100 |
| $0.80 | 1.25 | 1/4 | -400 |
The rules: decimal is 1 divided by the price. Fractional is profit over stake, so (1 minus price) over price. American odds above $0.50 use a minus sign: how much you must stake to win $100. Below $0.50 they use a plus sign: what $100 wins. Bookmaker odds also include the bookmaker's margin, so converting them back to a chance gives a number a bit too high.
Do Yes and No always add up to 100%?
Fair prices do. The prices you can actually buy at usually add up to a bit more, because of the spread. That extra is a cost of trading.
Say the best offer for Yes is $0.41 and the best offer for No is $0.61. Together that is $1.02, or 102%. The fair chance is somewhere in the middle, around 40% for Yes. On Hyperliquid, Yes and No share one merged order book, where buying Yes at p is the same as selling No at 1 minus p (>Hyperliquid docs, HIP-4), so the spread you see is the same from both sides. On a question with several outcomes, the Yes prices of all outcomes should add up to about 100% too.
When is a price worth paying?
Only when you believe the real chance is higher than the price. That gap is called your edge, and without it, buying is a slow way to lose the spread.
Here is the expected value, the average result if you could repeat the same bet many times. You put $2 on Yes at $0.40, so 5 shares.
| Your real chance of Yes | Average payout | Average result on $2 |
|---|---|---|
| 30% | $1.50 | -$0.50 |
| 40% | $2.00 | $0 |
| 50% | $2.50 | +$0.50 |
If your 50% is right, the bet is good on average, even though you still lose it half the time. If your 50% is wishful thinking and the real chance is 30%, you lose on average. The honest question is never "can it happen?" but "is it more likely than the price says?"
Is the market's chance accurate?
It is the best guess of the people trading, weighted by their money. It is often reasonable and sometimes wrong. A small market with few traders tells you less than a busy one.
A price reflects what traders know and believe right now. It can lag behind news, swing on one big order in a thin book, or reflect a crowd that all thinks the same thing. Use it as a starting point. When it disagrees with you, ask what the market might know that you do not.
Why do prices move before the end?
Because the chance changes as news arrives and as traders buy and sell. Your shares are worth their current price times their number, at any moment.
If you hold 5 Yes shares bought at $0.40 and the price rises to $0.60, they are worth $3 now. You can sell and take $1 of profit, or hold for $5 or $0 at the end. Selling early is how you take a gain or cut a loss without waiting for the result.
How do fees change the math?
Fees lower your payout, so the price you need to break even moves up. On Hyperliquid, opening a position is free, and in our check on October 18, 2026, about 0.07% was taken when selling or at settlement. CopyHype adds 1% to buy and 1% to sell early, and nothing at the result.
Elsewhere, fees can be real money. Polymarket's taker formula is C x feeRate x p x (1 - p) on some categories. For 100 shares of a sports market at $0.40, that is 100 x 0.05 x 0.40 x 0.60 = $1.20 on a $40 trade (>Polymarket docs, fees). Every platform: prediction market fees compared.
How does CopyHype show odds?
As a chance and a payout, side by side, before you tap. That is how predictions look in CopyHype.
For example, a market reads "40% · Yes · pays ×2.5", and the bet sheet shows "If Yes wins" with what your bet pays, after fees. No decimals to convert and no token names. Practice first with free practice money, from $10 a bet. How it works: Predictions in CopyHype.
Frequently asked questions
How do I convert a prediction market price to a probability?
The price in dollars is the probability. $0.40 means about 40%.
How much does $2 win at $0.25?
$2 divided by $0.25 is 8 shares, which pay $8 if you win, a $6 profit.
What are decimal odds of a $0.40 price?
2.50. Divide $1 by the price.
Why do Yes and No add up to more than $1?
Because of the spread: the best prices to buy each side sit a little above the fair price. The extra is a cost of trading.
Is a cheap side a good bet?
Not by itself. A side is cheap because the market thinks it is unlikely. It is only a good bet if you think the real chance is higher than the price.
Where do these facts come from?
The math is standard probability. Market rules come from Hyperliquid's and Polymarket's docs. Sources:
- >Hyperliquid docs: HIP-4 outcome markets
- >Chainstack developer guide: HIP-4 outcome markets trading
- >Polymarket docs: fees
Examples leave out fees unless stated. The term implied probability is in the glossary.
Keep reading
- Hyperliquid prediction markets (HIP-4 outcomes), explained simplyHow Hyperliquid HIP-4 outcome markets work: Yes and No prices as chances, a worked $10 example, USDC settlement, fees and what is listed.
- Crypto price predictions on Hyperliquid: how they work, honestlyHow Hyperliquid crypto price markets work: above a target at a deadline, which price decides, a $10 example with the payout, and the risks.
- Prediction market fees compared: Hyperliquid, Polymarket and KalshiWhat prediction markets really cost, dated October 2026: Hyperliquid HIP-4 and builder fees, Polymarket's taker formula, Kalshi, worked examples.