Prediction markets like Polymarket, Kalshi, and PredictIt use event contracts instead of sportsbook odds. A contract may trade at 40¢, 60¢, or another price in cents, and winning contracts typically settle at $1.00.
Use this Prediction Market Odds Converter to translate a Yes or No share price into American odds, decimal odds, market-implied probability, shares bought, gross payout, and gross profit before fees.
For example, buying a Yes share at 60¢ has a gross payout profile similar to -150 American odds or 1.67 decimal odds. The calculator shows the clean odds equivalent, but real trading results can differ because of fees, bid-ask spread, liquidity, and settlement rules.
Prediction Market Calc
Kalshi / PolymarketHow to Use the Calculator
This tool works as a two-way translator between financial trading math and sports betting math.
- Enter the Share Price: If you are looking at a market on Polymarket (e.g., “Fed Interest Rate Cut”), enter the current price in cents (e.g., 65).
- Note: You can also type in the Odds (Decimal or American) to automatically see the equivalent Share Price.
- Analyze the Conversion:
- Decimal / American Odds: See the equivalent betting line. For example, 65¢ equals -186 (American) or 1.54 (Decimal).
- Inverse Price: The calculator automatically determines the price and odds of the opposing side (“No”). If “Yes” is 65¢, “No” is 35¢ (+186).
- Simulate Investment: Enter your budget into the Investment Simulator. The tool calculates how many shares you can buy, the gross payout if the contract settles at $1.00, and your gross profit before trading fees, spread, slippage, and settlement costs.
Prediction Market Price to Odds Formula
If a prediction market share costs P cents and pays $1.00 when it wins, the decimal odds are:
Decimal Odds = 100 ÷ Share Price in CentsFor example, a 60¢ contract:
100 ÷ 60 = 1.67 decimal oddsFor American odds:
If price is below 50¢:
American Odds = ((100 − Price) ÷ Price) × 100
If price is above 50¢:
American Odds = −100 × Price ÷ (100 − Price)For implied probability:
Market-Implied Probability (%) = Share Price in CentsA 60¢ share implies a 60% market probability — before fees, spread, and execution costs.
Understanding the Math: Cents vs. Odds
In prediction markets, every contract pays out exactly $1.00 if the event happens and $0.00 if it does not. Therefore, the price can be read as a market-implied probability before fees, spread, liquidity limits, and settlement risk.
Example 1: The Favorite (High Price)
Market: “Will it rain tomorrow?” trades at 75¢.
- The Math: You pay $0.75 to win $1.00. Gross profit is 25¢ per winning share.
- Odds Equivalent: A 75% market-implied probability. In standard betting terms: 1.33 Decimal or -300 American.
- Investment: Investing $100 buys 133.3 shares. If it rains, gross payout is $133.30 (gross profit: $33.30 before fees).
Example 2: The Longshot (Low Price)
Market: “Candidate B wins the election” trades at 12¢.
- The Math: You pay $0.12 to win $1.00. Gross profit is 88¢ per winning share.
- Odds Equivalent: A 12% market-implied probability. In standard betting terms: 8.33 Decimal or +733 American.
- Investment: Investing $100 buys 833.3 shares. If they win, gross payout is $833.30 (gross profit: $733.30 before fees).
Prediction Market Odds Conversion Table
A quick reference for common share prices. The implied probability shown here is the market’s break-even rate before fees and spread.
| Share Price | Market-Implied Probability | Decimal Odds | American Odds | Gross Profit per $1 Risked |
|---|---|---|---|---|
| 5¢ | 5% | 20.00 | +1900 | $19.00 |
| 10¢ | 10% | 10.00 | +900 | $9.00 |
| 20¢ | 20% | 5.00 | +400 | $4.00 |
| 25¢ | 25% | 4.00 | +300 | $3.00 |
| 33¢ | 33% | 3.03 | +203 | $2.03 |
| 40¢ | 40% | 2.50 | +150 | $1.50 |
| 50¢ | 50% | 2.00 | +100 | $1.00 |
| 60¢ | 60% | 1.67 | -150 | $0.67 |
| 70¢ | 70% | 1.43 | -233 | $0.43 |
| 80¢ | 80% | 1.25 | -400 | $0.25 |
| 90¢ | 90% | 1.11 | -900 | $0.11 |
| 95¢ | 95% | 1.05 | -1900 | $0.05 |
Important Limits: Fees, Spread, Liquidity and Settlement
The calculator shows gross odds and gross profit. Real trading on Polymarket, Kalshi, or PredictIt is affected by several factors this tool does not model:
- Trading fees: Polymarket and Kalshi each have their own fee schedules; PredictIt charges 10% on profits and 5% on withdrawals. Always check the current fee schedule before trading.
- Bid-ask spread: The displayed price may be a midpoint. The actual executable price for a buy order can be higher.
- Liquidity: Thin markets can move significantly when you place a meaningful order.
- Settlement timing and rules: Some markets resolve quickly; others may take days or weeks. Resolution criteria can also be ambiguous in edge cases.
- Regulatory and legal availability: Polymarket, Kalshi, and PredictIt have different regulatory statuses and geographic availability.
This converter is best used to compare a prediction market price against a sportsbook line on the same outcome — not to project precise post-fee returns.
Frequently Asked Questions (FAQ)
How do you convert a prediction market price to American odds?
If the share price is below 50¢, use positive American odds: ((100 − price) ÷ price) × 100. If the share price is above 50¢, use negative American odds: −100 × price ÷ (100 − price). The calculator above does this automatically.
What are 60 cents in betting odds?
A 60¢ contract is equivalent to about 1.67 decimal odds or -150 American odds before fees and spread. If it wins, each share pays $1, so the gross profit is 40¢ per share.
Does a 60¢ price mean the event has a true 60% chance?
Not exactly. It is a market-implied probability based on trading prices, order books, and liquidity. The true probability may be higher or lower, and the displayed price may be affected by bid-ask spread, fees, low volume, or market rules.
Why do Yes and No prices not always add up to $1.00?
In a simplified binary market, Yes and No should sum to about $1.00. In live order books the executable buy prices can differ because of bid-ask spread, fees, and liquidity. If Yes is 60¢ and No is 42¢, the extra 2¢ acts like a trading cost or market margin.
Are Polymarket and Kalshi odds calculated the same way?
For a simple binary contract that pays $1.00 if it wins, the basic odds conversion is the same: price in cents can be converted into decimal or American odds. However, the platforms are not identical — fees, liquidity, market rules, settlement process, currency, and legal availability can differ. This calculator shows the gross odds equivalent rather than a full platform-specific trading result.
Does this calculator include trading fees?
No. The output is gross odds, gross payout, and gross profit before trading fees, spread, slippage, withdrawal costs, and settlement timing. Check the relevant platform fee schedule before trading.