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.
Updated Today
If the S&P 500 index value on Dec 31, 2026 at 4pm EST is above 9000, then the market resolves to Yes.
As of March 17, 2026, the Kalshi odds for Will the S&P 500 be between 4000 and 4199.99 on Dec 31, 2026 at 4pm EST? are: 7,200 to 7,399.99: 16%, 7,400 to 7,599.99: 11%, 7,600 to 7,799.99: 9%, 7,000 to 7,199.99: 7%, 7,800 to 7,999.99: 7%. These probabilities are derived from real-money trading and update in real time.
Will the S&P 500 be between 4000 and 4199.99 on Dec 31, 2026 at 4pm EST? is currently available on Kalshi. Check PredictMarketCap for cross-platform availability as new markets are added regularly.
Prediction market odds reflect the aggregate opinion of traders who risk real money on outcomes. The price of a share (e.g., 65¢) represents the market's implied probability (65%). Prices move as traders buy and sell based on new information, polls, and analysis.
