Prediction Markets / Contract entry
Prediction Market Profit Calculator
Shares, entry price and probability are your assumptions. A 40-cent YES share returns $1 if YES settles correctly and $0 otherwise.
Your inputs
Manual model only. Check current market rules, fee schedule, liquidity and settlement terms.
How to use this calculator: Contract entry
Shares, entry price and probability are your assumptions. A 40-cent YES share returns $1 if YES settles correctly and $0 otherwise.
Worked example: 100 contracts at $0.40 cost $40 before fees. Winning returns $100, a $60 profit. Losing loses the $40.
Important limitation
The market quote is a price, not a guarantee or your true win probability.
Manual model only. Check current market rules, fee schedule, liquidity and settlement terms.
What this number means
A positive expected result requires your own probability estimate to be accurate. The market price can reflect a spread, trading fees and disagreement between participants.
Use this as a settlement arithmetic check. It is most useful when you already know the contract side, entry price and quantity and want to separate gross payout from profit and subjective expected value.
Net settlement profit still depends on costs. Check the fee estimate before treating the quoted profit as net.
Common calculation mistake
Do not subtract the original purchase price twice when comparing profit. The $1 settlement payout is gross cash per winning share, not additional profit.
Related calculations
FAQ
Is a 65-cent YES contract a 65% chance?
It is a tradable price, not independent proof of a 65% probability. Your expected return requires a probability estimate of your own.
Why can break-even exceed 100%?
If entry costs plus cash fees exceed the maximum settlement payout, no probability can make that purchase profitable when held to settlement.
Is the displayed maximum loss always limited to my purchase?
For a fully paid $0/$1 binary contract without borrowing, loss is the purchase cost plus cash fees. Other contract structures are outside this calculator.
Important limitation
The market quote is a price, not a guarantee or your true win probability.
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