How to read Polymarket odds
A Polymarket price is the odds. Every share pays $1 if its outcome happens and nothing if it does not, so a Yes price of 36 cents means the market puts the chance at 36%. Buy at 36 cents, win, and you collect $1 for a 64 cent profit. Lose and you are out the 36 cents.
The boards above show the Polymarket price for each outcome as a percentage, the same price as American odds, and the Kalshi price for the same outcome beside it. Rivo reads every venue every five minutes and prints the time of the read under the title.
- Polymarket column: what Yes costs on polymarket.com right now, shown as the implied chance.
- American: the same Polymarket price written the way a sportsbook writes it.
- Kalshi column: what the same outcome costs to buy on Kalshi.
- 24 hours: how many points the outcome moved in a day, from Rivo's own hourly record.
Polymarket odds to American odds
The math takes one step. A favorite priced above 50 cents converts to a minus number: price divided by one minus price, times 100. An underdog priced under 50 cents converts to a plus number: one minus price, divided by price, times 100. A 20 cent share is +400. An 80 cent share is -400.
| Price of Yes | Implied chance | American odds | $100 pays if it wins |
|---|---|---|---|
| 5 cents | 5% | +1900 | $2000.00 |
| 10 cents | 10% | +900 | $1000.00 |
| 20 cents | 20% | +400 | $500.00 |
| 25 cents | 25% | +300 | $400.00 |
| 33 cents | 33% | +203 | $303.03 |
| 40 cents | 40% | +150 | $250.00 |
| 50 cents | 50% | −100 | $200.00 |
| 60 cents | 60% | −150 | $166.67 |
| 67 cents | 67% | −203 | $149.25 |
| 75 cents | 75% | −300 | $133.33 |
| 80 cents | 80% | −400 | $125.00 |
| 90 cents | 90% | −900 | $111.11 |
| 95 cents | 95% | −1900 | $105.26 |
The last column is the reason traders like low prices: $100 at 10 cents buys 1,000 shares and pays $1,000. The market wins that bet one time in ten, which is exactly what the price says. Fees at every price are worked through in Polymarket fees explained.
Polymarket is two exchanges
The name covers two separate products with separate accounts, balances and order books. The prices on this page come from polymarket.com.
| polymarket.com | Polymarket US | |
|---|---|---|
| Who trades there | Traders outside the United States | US residents |
| What you trade with | Crypto from your own wallet | Dollars |
| Regulation | No CFTC license | CFTC-regulated exchange |
| Trader identity | Every trade names a wallet | The exchange names no traders |
| In the Rivo terminal | Every market and trade, wallet records, manual trading from a connected wallet | Every market and trade, trading through a connected account |
The two books price the same event separately, so the odds differ between them. Each market's own page shows every venue that lists it, Polymarket US included. How Polymarket works covers the mechanics of both.
Why Polymarket odds differ from Kalshi
Two exchanges price the same event with two separate order books and two separate crowds. A gap of a point or two is normal. A bigger gap usually has one of three causes.
- Different rules. Each exchange writes its own contract, deadline and resolution source. Two markets with the same headline can settle differently in an edge case, and the price reflects that.
- Different traders. polymarket.com serves traders outside the US trading crypto. Kalshi serves US residents trading dollars. News reaches the two crowds at different speeds.
- Thin books. On a long shot with little resting money, one order moves the price several points until someone trades against it.
Each market's own page shows every venue's order book and marks the cheapest place to buy each outcome. Kalshi vs Polymarket compares the exchanges on fees, rules and access, and prediction market arbitrage works through when a gap beats the fees.
Every Polymarket trade names a wallet
This is what makes Polymarket odds different from any other odds board. Every trade on polymarket.com is public and tied to the wallet that made it. When a price moves, you can see who moved it, how much they put on, and how their last hundred bets turned out.
Rivo is the prediction market terminal for Kalshi, Polymarket, Polymarket US and Gemini. It ingests every market and every trade and turns that public record into something you can act on.
- Large trades as they print on the Polymarket whale tracker, with the wallet, the side and the entry price.
- Wallet records on the Polymarket leaderboard: profit, win rate against the odds paid, and the kind of market each trader is best at.
- Any address through the Polymarket wallet tracker: paste it and open the full record.
- Alerts on every new position a trader opens, and price alerts when a market crosses your level.
- Bots that copy a trader or run a signal on paper, built without code in the Polymarket bot builder.
The whole terminal is one subscription: $9 a week or $15 a month.
Frequently asked questions
What do Polymarket odds mean?
A Polymarket price is the market's chance of the outcome. A share pays $1 if the outcome happens, so a Yes price of 36 cents means a 36% chance. You pay 36 cents and collect $1 if you are right.
How do I convert Polymarket odds to American odds?
Above 50 cents, divide the price by one minus the price and multiply by 100 for a minus number: 80 cents is -400. Under 50 cents, divide one minus the price by the price and multiply by 100 for a plus number: 20 cents is +400.
Are Polymarket odds accurate?
Polymarket prices come from traders risking their own money against each other, and a price that is wrong pays whoever corrects it. Busy markets with deep order books track the true chance closely. Thin long shots move several points on one order.
Why are Polymarket odds different from Kalshi odds?
Each exchange has its own order book, its own traders and its own contract rules. A gap of a point or two is normal. Larger gaps come from different resolution rules, news reaching one crowd first, or a thin book.
Are polymarket.com and Polymarket US odds the same?
No. They are separate exchanges with separate order books, so the same event carries two prices. The boards on this page show polymarket.com. Each market's own page shows Polymarket US as well.
Can Americans see Polymarket odds?
Yes. Anyone can read the prices. Trading on polymarket.com is closed to US residents, who trade on Polymarket US, Kalshi or Gemini instead.
How often do the odds on this page update?
Rivo reads every venue's prices every five minutes and rebuilds the page at the same pace. The time of the last read is printed under the title.
Can I trade Polymarket odds through Rivo?
Yes. On polymarket.com you trade from Rivo's order ticket with your own browser-connected wallet, and on Polymarket US through your connected account. Rivo never holds your funds. The terminal costs $9 a week or $15 a month.