Polymarket Odds Converter
Instantly convert between probability, decimal, American, and fractional odds. Essential for Polymarket and sports betting analysis.
How to Use This Tool
Enter Any Format
Use the slider for probability, or type decimal/American odds directly.
See All Conversions
Instantly see equivalent odds in every format simultaneously.
Get Polymarket Price
See the exact share price and profit potential for Polymarket trades.
Understanding Odds Formats
Probability (Polymarket)
On Polymarket, share prices represent probabilities. A $0.65 share = 65% probability. If correct, you receive $1.00 per share. Use the profit calculator to model your exact return.
Decimal Odds
Total return per unit staked. Odds of 2.50 means you get $2.50 back for every $1 wagered ($1.50 profit + $1 stake). Formula: 100 / probability = decimal odds.
American Odds
Positive (+) shows profit on $100 stake. Negative (-) shows stake needed for $100 profit. +150 means $100 wins $150. -200 means stake $200 to win $100.
Fractional Odds
Shows profit relative to stake. 3/1 means $3 profit for $1 staked. Common in UK horse racing and traditional betting.
Odds Converter FAQ
How do I convert probability to Polymarket price?
Polymarket share prices directly represent probabilities as decimals. A 65% probability equals a $0.65 share price. If the event resolves Yes, you receive $1.00 per share. Formula: Polymarket price = Probability / 100. Use the slider above to convert instantly.
What is the difference between decimal odds and American odds?
Decimal odds show total return per $1 staked including your stake. Odds of 1.54 means you get $1.54 back for every $1 wagered ($0.54 profit). American odds use a +/- system relative to $100: +150 means a $100 stake wins $150 profit; -200 means you stake $200 to win $100 profit. Both formats express the same underlying probability.
How do Polymarket fees affect my actual payout?
Polymarket introduced dynamic taker fees in 2026 on some market categories. Geopolitics markets remain fee-free. When copying trades via Polyfollow, a 0.5% builder fee applies on taker orders. Maker orders are free. There is no subscription fee. Gas fees are covered. See the full breakdown on our Polymarket fees page.
Why do fractional odds look different from decimal odds?
Fractional odds only show the profit relative to stake, not the total return. 3/1 fractional odds (profit $3 on $1 stake) equals 4.00 decimal odds (total return $4 on $1 stake). Fractional odds are common in UK horse racing. For Polymarket, think in probability percentages and decimal equivalents for the clearest comparison.
Ready to Trade?
Now that you understand the odds, start trading on Polymarket. Copy successful traders automatically with Polyfollow.