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Data as of Aug 21, 2026, 5:40 PM UTC · policy pm-quality-3
Current implied probability
Up 99%+60.3pt
Market quality
80 / 100
High quality24h Volume
$17.9K
Liquidity
$20.2K
Medium liquidityBid / Ask
98.6% / 98.9%
Spread
0.3 pt
Tight spreadComments
0
Market data
Updated 4 minutes ago
Aug 20, 26, 12:00 PMAug 21, 26, 8:00 PM
Trends
Rules
This market will resolve to "Up" if the Close price for S&P 500 (SPY) on August 21, 2026 is higher than the Close price for S&P 500 (SPY) on the most recent prior trading day.
- This market will resolve to "Down" if the Close price for S&P 500 (SPY) on August 21, 2026 is lower than the Close price for S&P 500 (SPY) 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.
- Closing prices will be used exactly as published by Pyth, without rounding.
- If S&P 500 (SPY) does not trade at all during the regular session, the market will resolve 50-50.
Open markets
EquitiesPOLYMARKETWill Anthropic’s valuation hit __ by December 31?
- ↑$1.1T+3.6pt100%
- ↑$1.0T+2.4pt100%
- ↑$1.25T-0.9pt97%
+10 more outcomes
- Total Vol
- $3.9M
- 24h Vol
- $118.9K
KALSHINasdaq-100 price on Aug 21, 2026 at 4pm EDT?
- 28,030 or above99%
- 28,730 or above97%
- 28,710 or above97%
+97 more outcomes
- Total Vol
- $59.3K
- 24h Vol
- $59.3K
KALSHIS&P price on Aug 21, 2026 at 4pm EDT?
- 7,575 or above99%
- 7,570 or above99%
- 7,580 or above99%
+67 more outcomes
- Total Vol
- $49.1K
- 24h Vol
- $49.1K
POLYMARKETS&P 500 (SPX) Up or Down on August 21?
- Up+32.0pt82%
- Down-32.0pt18%
- Total Vol
- $44K
- 24h Vol
- $44K
KALSHIS&P close price end of 2026?
- 8,000 to 8,199.9915.4%
- 7,800 to 7,999.9912.7%
- 8,200 to 8,399.99-1.0pt10%
+24 more outcomes
- Total Vol
- $6M
- 24h Vol
KALSHINasdaq-100 price on Aug 21, 2026 at 11am EDT?
- 29,070 or above81%
- 29,100 or above71%
- 28,950 or above69%
+97 more outcomes
- Total Vol
- $36.9K
- 24h Vol
- $26.8K
- S&P 500 (SPX) Opens Up or Down on August 21?
- Nasdaq-100 close price end of 2026?
- S&P 500 ETF (SPY) Up or Down - Daily
- Largest Company end of December 2026?
- Largest IPO by market cap in 2026?
- S&P price on Aug 21, 2026 at 11am EDT?
- What will Robinhood Markets, Inc. (HOOD) hit Week of August 17 2026?
- STRC hits $100 by…
- S&P price range on Aug 21, 2026 at 4pm EDT?
- How low will the S&P get this year?
- What will Palantir Technologies Inc. (PLTR) hit Week of August 17 2026?
Frequently asked questions
- What are the current odds for SPY (SPY) Up or Down on August 21??
- Polymarket prices Up at 99% as of August 21, 2026.
- When does SPY (SPY) Up or Down on August 21? resolve?
- SPY (SPY) Up or Down on August 21? is scheduled to resolve on August 21, 2026.
- How is SPY (SPY) Up or Down on August 21? settled?
- Polymarket settles this market as follows: This market will resolve to "Up" if the Close price for S&P 500 (SPY) on August 21, 2026 is higher than the Close price for S&P 500 (SPY) on the most recent prior trading day.