Key data list for predicting the detonation of the World Cup: Exposure of roadside advertisements helps Kalshi lead the Polymarket, with the duopoly occupying over 95% of the market share BlockBeats News: On July 21st, the 2026 FIFA World Cup will become a watershed for the prediction market industry. According to BlockBeats, Kalshi's total platform trading volume during the World Cup reached $54.338 billion, approximately 2.6 times the $20.988 billion trading volume of Polymarket; The trading volume of World Cup related events is 13.591 billion US dollars, which is about 31% higher than Polymarket's 10.356 billion US dollars. In terms of user growth, the download volume of Kalshi APP reached 5.368 million times, far exceeding Polymarket's 2.136 million times. The exposure effect of advertisements on the sidelines of the arena is considered a key driver for Kalshi to widen the gap. The traffic of Polymarket website leads with 57.44 million times, but it has not been converted into an equal advantage in transaction volume and download volume. In terms of other platforms, Predict.fun has a total trading volume of 1.092 billion US dollars, with World Cup related transactions of 886 million US dollars; The total trading volume of Opinion is 1.137 billion US dollars, with approximately 561 million US dollars related to the World Cup; The total trading volume of Limitless is $446 million, with approximately $220 million related to the World Cup. From the perspective of data patterns, Kalshi and Polymarket have formed a duopoly pattern, with a combined market share of over 95%. There is still an order of magnitude gap in absolute size between small and medium-sized platforms. The World Cup has a significant "Super Bowl" effect as a predictor of the market - industry concentration further increases during the tournament, and brand exposure and user acquisition efficiency are becoming the core variables determining the next stage of competition.