CALCULATOR PREDICTION MARKETS

Prediction Markets Converter

A prediction market price is a probability quoted in cents. This reads it back as a percentage, and as the odds a sportsbook would post on the same outcome.

SHARP READ

A 65¢ contract is the market quoting 65.00%, which is -186 at a sportsbook. That is a translation, not a verdict — the book's number still has its fee inside, so strip that out before you decide which side of the screen holds the better price.

65.0% — IMPLIED PROBABILITY
SUCKER READ

Cheap contracts are where the value is. Twenty cents to win a dollar is upside a sportsbook won't give you.

The price

A contract settles at 100¢ if the outcome happens and if it does not, so the price you pay to hold it is the probability the market is quoting.

What the price says

Implied probability65.00%

The cents are the percent. Unlike a posted sportsbook price, this one is not padded with a book's margin — which is exactly why it is worth converting a book's number down to the same scale before you compare them.

The same price at a book

American-186
Decimal1.5385
Fractional1077/2000

How the conversion works

Price to probabilityprice = probability
Price to decimal100 / price
Price above evens to American −(price / (100 − price)) × 100
Price below evens to American +((100 − price) / price) × 100

Fractional odds are the profit part of the decimal price reduced to its smallest whole-number ratio, so an exact conversion sometimes prints an unfamiliar fraction rather than the tidy one a UK book would show.

WHAT THE NUMBER DOESN'T KNOW

A contract price is a probability before costs, not after. Venues charge differently — a Kalshi trading fee is largest around the middle of the range and smallest at the extremes — and the price on screen is not necessarily the price your order fills at. The arithmetic here is exact. Whether the number beats a sportsbook depends on the fee you pay to reach it and the depth sitting behind it in the order book.

What Is +EV Betting? why a losing night can still win · 8:00 No-Vig Fair Odds strip the book's fee before you compare the two screens Put the math on your sidePRICING