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Odds & payout calculator
Convert between American, decimal, and implied-probability odds, see your payout for a given stake, and strip the vig out of a two-sided market. Runs entirely in your browser.
Side A (e.g. "Yes")
Side B (e.g. "No")
Reading the numbers
| Term | Meaning |
|---|---|
| American odds | −150 means stake $150 to win $100 (plus your stake back); +130 means a $100 stake wins $130. |
| Decimal odds | Your total return per $1 staked. Decimal 2.00 = even money. |
| Implied probability | What the price says the market thinks the chance of that outcome is, before removing the vig. |
| Vig / overround | How far the two sides’ implied probabilities sum above 100% — the market’s built-in edge. |
Frequently asked questions
What is the difference between American, decimal, and implied-probability odds?
They are three notations for the same thing. American odds show how much you win on a $100 stake (positive) or how much you must stake to win $100 (negative). Decimal odds show your total return per $1 staked, including your stake back. Implied probability converts either into the market’s built-in chance of that outcome, as a percentage.
What is "vig" / "overround"?
In a two-sided market, the two sides’ implied probabilities should sum to 100% if the market were perfectly fair. In practice they sum to slightly more — that extra percentage is the vig (also called overround or juice), the house/market edge built into the prices. This calculator strips it out to show the "fair," no-vig probability for each side.
How does this relate to Predikt?
Predikt lets you trade prediction-market positions settled trustlessly on-chain, where prices are themselves implied probabilities. This calculator is a standalone reference tool for reading odds in any format — it does not place trades or connect to a wallet.
Is my stake or any wallet info sent anywhere?
No. Every number on this page is computed locally in your browser with plain arithmetic; nothing is transmitted, logged, or stored.