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NFL price gaps
The bets Arena matched on Kalshi, Novig and Polymarket, ranked by how far apart their prices are. Matches are made by rule, and some contracts settle differently: each row says where. Each row names the venue with the lowest price for each side. Open a bet to see every venue's price side by side.
How to read it
Arbitrage is the label for a pair that passes every test. Arbitrage here means buying YES on one venue and NO on another costs less than $1 after both venues' taker fees, on contracts that settle the same way, for the size shown, with both prices under 15 seconds old. Prices move. An order can fill at a worse price, or not at all.
Price gap, not arbitragemeans buying both sides costs less than $1 after fees, but something holds it back: the contracts settle differently, a match is not yet reviewed, a price is too old, a venue shows too little size or none, a venue is not open to US persons, a price is far from Kalshi's, there is no current Kalshi price to check against, or a fee could not be read. The reasons are listed under each row. Price gap means the venues disagree, but buying both sides costs $1 or more after fees. No gap means their prices agree.
Lowest to buy YES and Lowest to buy NO name the venue with the lowest price shown for that side, and how old that price is. A price more than a minute old is not shown. The best pair can use other venues: it names its own venues, prices, sizes and ages. It uses only venues a US user can use, unless no such pair has prices.
Polymarket's prices here come from its international exchange, which does not accept US persons. So by default Arena pairs only Kalshi and Novig for the arbitrage label.
Each Arena server reads Novig's public prices at most once a second, so each refresh reads a few Novig markets in turn and Novig prices cover only part of the list at a time. Prices older than 60 seconds drop off.
Arena is paper trading. It does not route orders to Kalshi, Novig or Polymarket and has no partnership with any of them. Each price is the venue's own. Fees are each venue's published taker fees as Arena works them out, and a venue can charge differently. How Arena fills paper trades is on /docs/execution.