How to read prediction market odds
By the Callquake team · Published · 2 min read
Last reviewed . Laws and platform rules change; check the sources linked below.
Prediction market prices look like money but read like probabilities. Here is how to turn a price into a chance, and how to tell a meaningful move from noise.
Price = chance
A “Yes” contract pays $1 if the event happens. So a price of 62¢ means traders put the chance at about 62%. The “No” side trades near the remainder, about 38¢.
| “Yes” price | Implied chance | Pays if right (per $1 contract) |
|---|---|---|
| 10¢ | 10% | 90¢ profit |
| 50¢ | 50% | 50¢ profit |
| 85¢ | 85% | 15¢ profit |
Points, not percent
When a market goes from 40% to 55%, we call that a move of +15 points. Saying it rose “37.5%” is technically true but confusing, so Callquake always reports changes in percentage points. We flag a move as big when it reaches 8 points within 1 hour or 12 points within 1 day.
Which price? Bid, ask and last trade
Every market has a bid (the best price someone will pay) and an ask (the best price someone will sell at). We use the midpoint between them when the gap is 10¢ or less. When the gap is wider, the midpoint is unreliable, so we use the last traded price instead. Details are on our methodology page.
How much to trust a number
- Volume. A market with millions of dollars traded in a day is harder to push around than one with a few thousand. We only track markets with at least $5,000 of 24-hour volume.
- Spread. A wide gap between bid and ask means few people are willing to trade near the quoted price.
- Fees. Trading costs can keep prices from moving all the way to the true chance. Kalshi’s fee, for example, is highest near 50¢ and lowest near 1¢ or 99¢ (Tech Insider, “What is Kalshi?” (2026)).
- Rules. Read how the market resolves. Two markets that sound alike can settle on different sources or dates.
Comparing Kalshi and Polymarket
When the same question trades on both platforms, Callquake shows each price and a combined figure weighted by trading volume. A gap of a few points is normal: the traders, fees and rules differ. A large gap usually means the two markets are not quite the same question. See Kalshi vs Polymarket.
A quick checklist
- Read the price as a chance, not a prediction.
- Check volume and spread before trusting a move.
- Look for the news behind the move. That is what our Why it moved archive is for.
- Remember that 80% events fail one time in five.