State of the OddsLive prediction-market odds, side by side
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How prediction-market prices work

A contract on Kalshi or Polymarket pays $1 if the event happens and $0 if it does not. If it trades at 62¢, buyers are collectively paying as if the odds were about 62%. That is the whole trick: the price is the crowd's probability, and it moves whenever someone is willing to pay more or less.

Why the two exchanges disagree

Kalshi is a US-regulated exchange that trades in dollars and is open to Americans aged 21 and over in most states. Polymarket's global exchange trades in a dollar stablecoin and serves users outside the US; a separate Polymarket US app launched in 2026 with its own order book. The Polymarket prices on this site are from the global exchange, which carries the most volume. Different traders, different fee schedules, different amounts of money on each side. A gap of one to three points is normal noise. A gap of ten points means two pools of money have not agreed, which usually closes within days as traders arbitrage it, and occasionally does not because one exchange has a rule the other lacks.

What State of the Odds shows

  • Price: the last traded price for the Yes side of each contract, shown as a percentage.
  • Gap: Kalshi minus Polymarket, in points, for the same outcome.
  • Open interest (Kalshi): the dollar value of contracts currently held. Volume (Polymarket): dollars traded over the life of the market. Both are a rough guide to how much money stands behind a price. Thin markets move on small trades.
  • 7-day change: the price now against the last daily close seven days ago.

What the odds cannot tell you

A 90% price is not a guarantee, and a 10% price is not zero. Markets are good at pooling public information quickly and bad at things nobody knows yet. They also carry small biases: long shots tend to trade a little higher than their true odds, and prices near the deadline can be pushed by a single large order.

Fees

Both exchanges charge trading fees that vary with the price of the contract. State of the Odds shows prices before fees. Check each exchange's fee page before trading.