How to read Polymarket odds
Last updated · how we verify
The price is the probability. A share costing 63¢ means the market
implies a 63% chance, and it pays $1 if the outcome happens — so you profit 37¢ per share. Decimal odds
are 1 ÷ price. Yes and No prices sum to about $1 because together they always pay exactly $1,
and the gap between them is the spread rather than a bookmaker's margin.
The one thing to understand
Every Polymarket share pays exactly $1 if its outcome happens, and $0 if it does not. So the price is the probability: a share costing 63¢ is the market saying 63%.
That makes the arithmetic unusually clean:
- Cost: price × shares.
- Payout if right: $1 × shares.
- Profit if right: (1 − price) × shares.
- Implied probability: the price itself.
Conversion table
| Price | Implied probability | Profit per share | Decimal odds | American odds |
|---|---|---|---|---|
| 5¢ | 5% | $0.95 | 20.00 | +1900 |
| 20¢ | 20% | $0.80 | 5.00 | +400 |
| 40¢ | 40% | $0.60 | 2.50 | +150 |
| 63¢ | 63% | $0.37 | 1.59 | -170 |
| 80¢ | 80% | $0.20 | 1.25 | -400 |
| 95¢ | 95% | $0.05 | 1.05 | -1900 |
Where value comes from
You are not trying to pick winners. You are trying to find prices that are wrong. If you believe an outcome is 70% likely and the market prices it at 55¢, that gap is your edge — whether or not this particular event goes your way.
- Form your own probability first, before looking at the price. Anchoring to the market price defeats the exercise.
- Compare, then act only on a meaningful gap. Small edges are consumed by the spread and the fee.
- Account for the fee at your price point. A 2-point edge on a 50¢ contract is thinner than it looks once the peak fee applies.
- Read the resolution criteria. A price can look wrong only because you have misread what the market is actually asking. Why this matters →
Buying "No" at 37¢ is the same position as selling "Yes" at 63¢. If one side looks badly priced, check the other — the better fill is sometimes on the opposite side of the same market.
Availability varies by jurisdiction. 18+. Event contracts carry risk of loss.
You appear to be in the US. Polymarket’s international exchange blocks US IP addresses — use Polymarket US, the CFTC-regulated exchange, instead. See what’s available in your state.
Why this beats reading a sportsbook line
A sportsbook quotes odds with margin already inside them, so the implied probabilities across all outcomes sum to more than 100% and you cannot see the cut. On an exchange the prices are what participants agree and the fee is charged separately, so you can see exactly what you are paying. Full comparison →
Questions
What does a 63 cent contract mean?
The market is pricing a 63% chance of that outcome. You pay 63¢ per share and receive $1 per share if it resolves yes, so your profit is 37¢ per share — a return of about 59% on the amount risked.
How do I convert Polymarket prices to betting odds?
Decimal odds are 1 ÷ price. So 63¢ is 1.59 decimal. For American odds: at 50¢ or above it is −(price ÷ (1 − price)) × 100; below 50¢ it is +((1 − price) ÷ price) × 100.
Do Yes and No always add to $1?
Close to it, because a Yes and a No share together always pay exactly $1 on resolution. The gap between the best bid and best ask is the spread — and unlike a sportsbook's overround, that spread is set by other traders, not by the house.
Where does the fee come in?
The taker fee is charged on top, and it depends on both the category and the price: fee = shares × feeRate × price × (1 − price). Because it peaks at 50¢, trading a coin-flip costs proportionally more than trading a near-certainty. Fee detail.
Related
Fees
How price affects what you pay.
vs sportsbooks
Visible fee vs hidden margin.
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All figures on this page verified 17 August 2026 against primary sources where reachable. Unconfirmed values are marked.