S&P 500 Index · Will the S&P 500
S&P 500 Index is priced at 42¢ on Kalshi. Current book: 36¢ bid, 39¢ ask, 3¢ spread. This outcome ranks #2 of 2 inside Will the S&P 500.
Price history
42¢ current
+16¢Contract brief
If S&P 500 Index performs above S&P 500 Equal Weight Index during 2026 by 0.001% rounded to the nearest 3rd then the market resolves to Yes.
Outcome
S&P 500 Index
Rank
#2 of 2
Leader
S&P 500 Equal Weight Index 67¢
Range
36¢-67¢
Family volume
$0
Identifier
KXINXVSINXEW-26DEC31-INX
Aug 9, 2026, 8:38 AM UTC · 19m ago
Implied probability
Bid
36¢
Ask
39¢
Spread
3¢
Reported volume
$874
Family rank
#2 of 2
2 outcomes · Will the S&P 500
Closes
Jan 1, 2027
Family volume
$0
Orderbook snapshot
36 / 39¢
Contract terms
What resolves this market.
YES condition
If S&P 500 Index performs above S&P 500 Equal Weight Index during 2026 by 0.001% rounded to the nearest 3rd then the market resolves to Yes.
Venue
Kalshi
Closes
Jan 1, 2027
Identifier
KXINXVSINXEW-26DEC31-INX
Event family
Will the S&P 500.
The same race as a probability stack: rank, volume, and where this contract sits against the other outcomes.
Total volume
$0
Outcomes
2
Highest price
S&P 500 Equal Weight Index 67¢
Current share
—
Indicators
Yield, cliff risk, volatility, and regime.
Regime
neutral
Score
0.5
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SimpleFunctions context
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Prediction Market Index
Market-wide volatility, geo risk, breadth, and activity around this contract.
Market Screener
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Event Probability API
Read 42% as a structured event probability object for agents and apps.
Realtime Data API
Prices, orderbooks, movement, heat, and liquidity indicators across venues.
World State API
Compact market-aware context packets for agent sessions and scheduled refresh.
Hedging Workflows
Map a thesis or exposure to candidate event markets and monitoring paths.
How we compute these odds
SimpleFunctions aggregates live prediction-market contracts from Kalshi and Polymarket. Each slug groups contracts that resolve on the same underlying event, identified by venue event_id.
For binary slugs, the headline probability is the liquidity-weighted mid-price across all bound contracts. For multi-outcome slugs (e.g. elections with 3+ candidates), the headline is the leader’s price; we never arithmetically average disjoint outcomes — that would produce a number with no real-world meaning.
Snapshots refresh every 5 minutes during market hours; daily aggregates are computed at 04:00 UTC. The 30-day sparkline is drawn from per-ticker daily means stored in market_indicator_daily; 24h delta and movement events are derived from the same source.