Blog
Notes on cross-venue prediction markets, how the matching works, and building on the API.
USA vs Belgium: two goals two minutes apart, priced in opposite order
A World Cup equalizer and the goal that answered it two minutes later moved Kalshi and Polymarket in opposite order. The two books did not agree on Belgium's price for about six minutes.
A mispricing between Kalshi and Polymarket lasts about 10 seconds
We measured how long price gaps between Kalshi and Polymarket stay open before the two books converge. Half close within about nine seconds.
Argentina vs Egypt: Kalshi followed Polymarket within seconds
We checked whether the price gaps between Kalshi and Polymarket on Argentina-Egypt were a real trading opportunity. Against the volume moving through that exact market, they were not.
Why every arb carries an executable size
An arb that only exists for one contract is not one you can trade. Here is how we size every opportunity to the depth behind it.
Introducing dino.markets
One API for Kalshi and Polymarket sports markets, matched across both books, with the arbitrage that opens between them.