TOTAL VOLUME:
$61.9b
24H VOL:
$249,705,498
24H TRANSACTIONS:
600,069,390
OPEN INTEREST:
$1,354,509,605
579,516
Markets across
14,317
events
MATCHED EVENTS:
4,116
PLATFORM COVERAGE:
4
Polymarket:
50%
VS.
Kalshi:
50%
Nasdaq 100 (NDX) Up or Down on April 21? Odds & Prediction Markets
Closed: Apr 21, 7:00 PM EST
Kalshi
Description
This market will resolve to "Up" if the official Nasdaq 100 Index closing price for Nasdaq 100 (NDX) on Tuesday, April 21, 2026 is higher than the official Nasdaq 100 Index closing price for NDX on the most recent prior trading day. This market will resolve to "Down" if the official Nasdaq 100 Index closing price for Nasdaq 100 (NDX) on Tuesday, April 21, 2026 is lower than the official Nasdaq 100 Index closing price for NDX on the most recent prior trading day. E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day. If the two specified closing prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding. If NDX does not trade at all during the regular session, the market will resolve 50-50. If either of the relevant days are shortened (for example, due to a market holiday schedule), the official closing price published by Nasdaq 100 Index for that shortened session will still be used for resolution. If either of the relevant days have no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price. The resolution source for this market is the Wall Street Journal, specifically the Close values published by the WSJ under "Historical Prices". US: https://www.wsj.com/market-data/stocks EMEA: https://www.wsj.com/market-data/stocks/emea ASIA: https://www.wsj.com/market-data/stocks/asia
PredictionHero - Resolution Divergence Alerts (RDA)
Divergence Detected
Issue:
Polymarket and Kalshi measure fundamentally different events: Polymarket resolves on day-over-day price movement (Up/Down vs prior trading day), while Kalshi resolves on absolute index level thresholds. These are logically incompatible—the same April 21 close can satisfy multiple Kalshi thresholds while producing a single Polymarket outcome, and Kalshi's 60 overlapping conditions create internal logical contradictions.Hero Tip:
Do not cross-hedge these markets. A Polymarket 'Up' bet (NDX closes higher than April 20) is NOT equivalent to any single Kalshi threshold bet. Kalshi's 60 redundant conditions all resolve identically once the index level is known, making individual Kalshi contracts economically identical—avoid taking opposing positions on different Kalshi thresholds, as they will all settle the same way.Critical Divergence Points:
Polymarket:
Resolves YES ('Up') if April 21 closing price > April 20 closing price; NO ('Down') if April 21 < April 20; 50-50 if equal. Compares two specific dates only. Source: Wall Street Journal Historical Prices. Key quote: 'This market will resolve to Up if the official Nasdaq 100 Index closing price for Nasdaq 100 (NDX) on Tuesday, April 21, 2026 is higher than the official Nasdaq 100 Index closing price for NDX on the most recent prior trading day.'Kalshi:
Resolves YES if end-of-day NDX on April 21 exceeds any of 60 different absolute price thresholds (ranging from 23599.99 to 29499.99). All 60 conditions are logically redundant—once the April 21 close is known, either all 60 resolve YES or all 60 resolve NO, depending on whether the index is above the lowest threshold (23599.99). Key quote: 'If the end-of-day Nasdaq 100 index value on April 21, 2026 is above [threshold], then the market resolves to Yes.'
Related events
Follow the signals, not the noise
Get insights on market conviction, notable shifts, and what the data is quietly signaling.