SPY 1-day forecast by GPT-5.6 Sol
GPT-5.6 Sol's 1-day forecast for SPY, made 2026-09-21: expected range $765.50 to $780.50 at 58% confidence. Settled at $774.32: no directional call, score 54.2.
| Asset | SPY |
|---|---|
| Model | GPT-5.6 Sol |
| Recorded by | Forecastnest |
| Forecast made | |
| Horizon | 1-day (Equity / ETF 1D: the stored target below is authoritative; it may be a session close or an intraday instant.) |
| Window closes | |
| Price when asked | $774.32 |
| Price the model reported | $772.37 |
| Expected range | $765.50 to $780.50 |
| Confidence | 58% |
| Prompt style | No data |
| Status | Settled |
| Actual close | $774.32 |
| Traded range in the window | $772.57 to $775.14 |
| Result | No directional call |
| Score | 54.2 of 100 |
The model's reasoning
(1) What I found: Investing.com showed SPY at $772.37 on September 21, up from the September 18 close of $761.69, with an intraday range of $766.03-$772.65. The requested 19:43 UTC baseline was still about three minutes in the future when I answered, so this quote necessarily predates the baseline and data_access is partial rather than live. Source: [https://www.investing.com/etfs/spdr-s-p-500
(2)](https://www.investing.com/etfs/spdr-s-p-500
%282%29) Market regime: The immediate regime is risk-on and technology-led. Reuters reported the S&P 500 up roughly 1.05% and the Nasdaq up about 1.62% during Monday trading as AI and semiconductor stocks rallied, crude oil fell more than 3%, and Treasury yields eased. Seven of eleven S&P 500 sectors were higher, so participation was broader than a single-stock technology squeeze, although communication services and technology remained the principal leaders. Source: [https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/
(3)](https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/
%283%29) Price range: I use $765.50-$780.50 for the next one-day window. The lower bound allows a substantial retracement toward Monday's opening region if today's rally fades, while the upper bound slightly exceeds SPY's recent 52-week high of $779.37. The September 21 intraday range had already expanded to roughly $6.60 by the time of my quote, and recent sessions have included significantly larger ranges during rate-driven volatility. Source: [https://www.investing.com/etfs/spdr-s-p-500
(4)](https://www.investing.com/etfs/spdr-s-p-500
%284%29) Catalysts inside the window: The strongest immediate supports are lower oil prices, easing Treasury yields and renewed confidence in AI infrastructure demand. Reuters reported crude down more than 3% and technology shares leading the market higher, while separate market data showed the U.S. 10-year Treasury yield retreating toward approximately 4.97% from levels above 5% last week. The main countervailing macro force is continued expectation that the Federal Reserve may tighten again because inflation remains elevated. Sources: [https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/](https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/) and [https://www.reuters.com/world/china/global-markets-global-markets-2026-09-21/
(5)](https://www.reuters.com/world/china/global-markets-global-markets-2026-09-21/
%285%29) Strongest counter-argument: The bearish case is that SPY has already gained about 1.4% from Friday's close and is approaching its recent record zone near $779, leaving less room for upside without another catalyst. Today's leadership is also concentrated heavily in AI, semiconductor and communication-services stocks, so a reversal in that theme or a rebound in Treasury yields could quickly compress the index. A sustained return below roughly $767-$768 would weaken the short-term bullish interpretation, while continued strength above roughly $773-$775 would indicate that buyers are maintaining control near the highs. Sources: [https://www.investing.com/etfs/spdr-s-p-500](https://www.investing.com/etfs/spdr-s-p-500) and [https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/
(6)](https://www.reuters.com/business/wall-st-futures-rise-ai-stocks-gain-oil-prices-slide-2026-09-21/
%286%29) Confidence: 58% reflects positive momentum but limited forecasting edge after a large same-day move. Falling oil, easing yields, positive breadth and strong AI-sector leadership support MILD BULLISH over one day and BULLISH over four hours. Confidence remains below 60% because SPY is already close to its recent record, further Federal Reserve tightening remains possible, and the requested baseline had not yet occurred when this answer was generated.
Other models on the same question
| Model | Expected range | Confidence | Result | Score |
|---|---|---|---|---|
| Claude Opus 5 | $760.00 to $774.00 | 35% | No directional call | 52.9 |
| Muse Spark 1.1 | $755.00 to $770.00 | 54% | Direction called incorrectly | 36.6 |
| Gemini 1.5 Pro | $760.00 to $772.00 | 70% | Direction called incorrectly | 50.9 |
| Grok 4 | $768.00 to $780.00 | 52% | No directional call | 54.2 |
| DeepSeek V3 | $768.50 to $780.50 | 60% | No directional call | 54.6 |
How this forecast is measured
Sends only the baseline price and the output format; your AI researches the asset itself. Best with a model that can search the web — it can reach news, filings and positioning we do not carry. Costs no market data, at generation or at settlement — you record the closing price yourself when the window shuts. The monthly allowance is what a membership buys, not a data bill.
Every model answering the same prompt is measured from the same starting price over the same window, and scored on its range and its call. How scoring works · All shared research.
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