PREDICTION MARKETS
Polymarket and Kalshi Arbitrage Scanner vs Sportsbooks
Polymarket and Kalshi price by trading, not by analysts. In 30 days: 438K surebets with Polymarket and 83K with Kalshi; 7.5% and 6.4% lasted over a minute.
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- 29,253Polymarket surebets over a minute
- 423,572surebets with Polymarket
- 2.0 smedian lifetime with Polymarket
Dozor data for October 11 – November 10, 2026 — methodology
A prediction market is an exchange where an outcome's price comes from traders' deals: a “Team A wins” contract trades between $0 and $1, and a price of $0.45 means odds of 2.22. There's no analyst moving the line after every round. Over 30 days, October 6 – November 5, 2026, Dozor recorded 438,206 surebet episodes involving Polymarket and 82,508 involving Kalshi: Polymarket takes part in 9.1% of all episodes (4,829,879 in total, 1,397,673 distinct surebets). Surebets with an exchange last a minute more often: 7.5% for Polymarket and 6.4% for Kalshi versus 3.9% across all books.
Who Polymarket forms surebets with
| Pair | Surebets in 30 days | Over a minute | Median life |
|---|---|---|---|
| Duel and Polymarket | 59,517 | 12.0% | 2.1 s |
| 1xBet and Polymarket | 59,329 | 4.7% | 2 s |
| GGBet and Polymarket | 18,793 | 14.3% | 4 s |
| CSGOPositive and Polymarket | 15,924 | 13.1% | 4 s |
| Thunderpick and Polymarket | 12,342 | 8.2% | 2 s |
The table covers international books. The median lifetime of a surebet involving Polymarket is 2 seconds, as across the whole scanner, but 7.5% of Polymarket surebets last over a minute versus 3.9% on average; the Duel–Polymarket pair produces the most long-lived ones: 7,113 in 30 days. Kalshi had 82,508 episodes over the same window, with a median lifetime of 2 seconds; among international books it was most often paired with 1xBet and Duel. The GGBet, CSGOPositive and Thunderpick rows come from a query to the same history over the same window. The mechanics, fees and a worked example are in the article on Polymarket and Kalshi arbitrage with sportsbooks.
How an exchange differs from a bookmaker
- Volume is capped by order book depth. You can buy as many contracts as sit at the price you need. Dozor shows the depth and offers a minimum-depth filter.
- Priced in dollars, settled in crypto. Polymarket settles in pUSD, a token backed by USDC; Kalshi runs in US dollars. The exchange rate, the platform fee and the bid-ask spread are all included in the ROI calculation.
- Separate market settlement rules. An exchange contract is defined in text: what counts as a win, what happens if the match is cancelled. It may differ from a bookmaker's rules for the same match.
- Execution is a trade, not a bet. You can buy a contract at the price you need as long as there's volume in the order book. A large amount will move the price.
How Dozor works with exchanges
Polymarket and Kalshi are connected like regular books: their contracts are mapped to the same markets as bookmaker lines and take part in the surebet search on equal terms. In the card, the exchange leg shows the contract price, the equivalent odds and the order book depth. The minimum order book depth filter cuts out surebets you can't get into with the stake you need.
Terms
Tools
Frequently asked questions
Are there direct surebets between Polymarket and Kalshi?
Both markets trade the same major events, and discrepancies between them do happen. In esports, most of Polymarket's surebet volume is against bookmakers, not against Kalshi.
Why do exchange surebets live longer?
The price is moved by traders, not by a bookmaker's algorithm. Until someone places a new order, the old price stays.
What is order book depth?
The volume of contracts available at the price the surebet was calculated from. See the term in the glossary.
Live figures for Polymarket and its pairs are in the Bookmakers section.
Data on this page: Dozor surebet history for October 6 – November 5, 2026, 4,829,879 episodes, 1,397,673 distinct surebets; how we count is in the methodology.