Prediction markets trade $100.2B in contracts over the last 30 days, with Kalshi handling 76% of it and its volume up 56% against the 30 days before, on DeFi Rate's volume tracker

Contract volume reaches $100.2B

Prediction markets recorded $100.2B in contract volume over the last 30 days, according to DeFi Rate’s volume tracker, as reported on Oct 17, 2026, at 3:54 AM ET. Kalshi accounted for 76% of that total.

Kalshi’s volume increased 56% compared with the preceding 30 days, according to the tracker. The figures show both its share of recent trading and its growth between the two periods; they do not establish the growth rate for prediction markets overall.

Face value differs from dollars paid

The $100.2B figure measures contracts at their $1 face value, rather than the amount traders spent to acquire them. DeFi Rate puts the dollars actually paid at $25.3B—a distinction that matters when comparing reported prediction-market activity with cash-based measures of trading.

The tracker also reports $3.4B in volume over the last 24 hours. That provides a shorter-window measure of activity, but the supplied figures alone do not establish whether daily trading is accelerating or slowing.

What it means for prediction markets

• Measurement matters: The $100.2B headline is a face-value contract measure. The corresponding dollars actually paid were $25.3B.
• Activity is concentrated: Kalshi handled 76% of the reported 30-day volume, making its trading activity central to the aggregate figure.
• Growth is platform-specific: Kalshi’s 56% increase applies to its own volume against the preceding 30 days, not necessarily to the wider market.
• Volume is not a probability signal: These totals describe trading activity, not changes in the implied likelihood of any particular outcome.