Polymarket$2.32BOIOpen interest: sum of pool liquidity across all active markets, reported by the Polymarket API.
Kalshi$350.67MOIOpen interest: total contracts outstanding across all active markets, reported by the Kalshi API.
Limitless$18.48MOIOpen interest: estimated from total volume traded (USDC). Limitless does not report a separate OI metric.Compare World Baseball Classic Winner 2026 prediction market odds side by side across Polymarket, Kalshi. Platforms show similar odds, with an average spread of just 0.9pp. Close agreement often signals strong market consensus. With $1.82M in combined trading volume across 21 outcomes, this is one of the most actively traded cross-platform prediction markets.
| Outcome | Polymarket | Kalshi | Spread |
|---|---|---|---|
U United States | - | 71%-4.0 | - |
 USA | 71%-0.5 | - | - |
|
30%+0.8 |
30%+11.0 |
| 0.3pp spread |
Canada | 0%±0 | 2%±0 | 1.9pp spread |
Czechia | 0%— | 1%±0 | 0.9pp spread |
Dominican Republic | 0%+1.5 | 1%±0 | 0.9pp spread |
Netherlands | 0%±0 | 1%±0 | 0.9pp spread |
Israel | 0%±0 | 1%±0 | 0.9pp spread |
Nicaragua | 0%— | 1%±0 | 0.9pp spread |
Brazil | 0%±0 | 1%±0 | 0.9pp spread |
Great Britain | 0%— | 1%±0 | 0.9pp spread |
Panama | 0%±0 | 1%±0 | 0.9pp spread |
Chinese Taipei | 0%±0 | 1%±0 | 0.9pp spread |
Korea | 0%±0 | 1%±0 | 0.9pp spread |
Colombia | 0%±0 | 1%±0 | 0.9pp spread |
Japan | 0%+1.5 | 1%±0 | 0.9pp spread |
Puerto Rico | 0%±0 | 1%±0 | 0.9pp spread |
Mexico | 0%-2.4 | 1%±0 | 0.9pp spread |
Cuba | 0%— | 1%±0 | 0.9pp spread |
Italy | 0%±0 | 1%-7.0 | 0.9pp spread |
Australia | 0%±0 | 1%±0 | 0.9pp spread |
