Prediction Markets / Paired outcomes
YES/NO Arbitrage Calculator
Enter executable YES and NO ask prices for the same exhaustive event, matched quantity and both fees. Both contracts settle to a combined $1.
Your inputs
Manual model only. Check current market rules, fee schedule, liquidity and settlement terms.
How to use this calculator: Paired outcomes
Enter executable YES and NO ask prices for the same exhaustive event, matched quantity and both fees. Both contracts settle to a combined $1.
Worked example: YES ask 0.47 and NO ask 0.49 cost $0.96 total. If both execute and rules match, $0.04 gross per pair remains before fees.
Important limitation
Two markets with different event wording or resolution sources do not provide riskless arbitrage.
Manual model only. Check current market rules, fee schedule, liquidity and settlement terms.
Matched contracts are essential
YES and NO must pay a combined $1 for every matched pair under exactly the same settlement terms. Different platforms can describe a similar event while resolving it differently.
This is a consistency test for two complementary contracts. It does not search markets. The result is useful only if wording, resolution source, quantity and settlement are genuinely matched.
Both contracts need sufficient quantity at their quoted asks. Model execution depth for the pair.
Account for the second leg
A cheap YES ask without a filled NO ask leaves directional exposure. Fees and slippage can turn a superficially positive price gap into a loss.
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FAQ
When are YES and NO complementary?
The contracts must come from the same exhaustive event with identical settlement definitions and cover every possible resolution, including exceptions.
Can I arbitrage prices displayed by two different platforms?
Only after matching their rules, settlement source, dates, execution, fees and payout currencies. Similar wording alone is insufficient.
What happens if just one leg fills?
You are left with a directional exposure, not a locked payout. A quoted theoretical spread does not confirm the second fill.
Important limitation
Two markets with different event wording or resolution sources do not provide riskless arbitrage.
Polymarket complementary YES/NO tokens · Kalshi market orderbook