UK guide
How Prediction Market Probabilities Work
How contract prices translate into percentages and what liquidity, spreads and fees do to the signal.
Published 1 September 2026Reviewed 18 September 2026
From price to percentage
A YES contract at 0.58 is commonly read as a 58% market-implied probability. That interpretation is clearest in a liquid binary market with straightforward settlement.
Why the price changes
New evidence changes what traders are willing to pay. The visible price moves when incoming orders consume the best available offers or when a market maker adjusts its quote.
Three reasons to be cautious
A probability can look more precise than the market deserves.
- Low liquidity lets one trade move the price
- Wide spreads leave no single fair price
- Fees and access restrictions can distort participation