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Polymarket odds converter

Type a Polymarket share price, American odds, decimal odds, a fraction or a probability. Every other format updates, with the price after the taker fee.

Polymarket odds converter illustration

How a Polymarket price maps to odds

A Polymarket share pays $1 if the outcome happens and nothing if it does not. The price in cents is the market’s implied probability: a 62¢ share says 62%.

Decimal odds are 1 divided by the price. American odds follow from the decimal: under 2.00 the line is negative, at 2.00 and above it is positive.

d = 100 ÷ cents; A = 100 × (d − 1) when d is 2 or more, otherwise −100 ÷ (d − 1)

Taker orders pay a fee on Polymarket, so the price you actually pay is a little higher than the quote. On a sports market at the 0.05 rate a 62¢ share costs about 63.2¢, which is −172 instead of −163. See the Polymarket fee calculator for the formula.

Worked example

Worked example: Bills at 62¢ on Polymarket

  1. Implied probability: 62%
  2. Decimal: 1 ÷ 0.62 = 1.61
  3. American: −100 ÷ 0.61 = −163 · Fractional: 19/31
  4. Taker fee at 0.05: 0.05 × 0.62 × 0.38 = 1.18¢, so the real price is 63.2¢

After the fee the Bills are decimal 1.58, or −172.

Compare that −172 with a sportsbook line. If DraftKings has the Bills at −150, the book pays more for the same side, and the no-vig calculator tells you which of the two is closer to fair.

Frequently asked questions

What does a Polymarket price mean in odds?

The price in cents is the implied probability. 40¢ is 40%, which is decimal odds of 2.50 and American odds of +150.

How do I convert Polymarket cents to American odds?

Divide 100 by the price in cents to get decimal odds. If the decimal is 2.00 or more, American odds are (decimal − 1) × 100. If it is under 2.00, American odds are −100 ÷ (decimal − 1).

Do Polymarket fees change the odds?

Yes, for taker orders. The fee is shares × rate × price × (1 − price), so the effective price is higher than the quote and the odds are a little shorter. Resting maker orders pay no fee.

Is a Polymarket price the true probability?

It is the market’s price, not a guarantee. Thin markets and late news can leave it off. Arbs puts its own model probability next to every Polymarket price so you can see where they disagree.

Read the guide: How to read Polymarket sports odds

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