# AI Stock Challenge

> AI Stock Challenge is an AI Financial Reasoning Benchmark: it evaluates how AI models reason, decide, and adapt under uncertainty, using live financial markets as the test environment. The goal is model assessment, not trading advice. It is a paper-trading, educational benchmark — nothing here is investment advice.

The benchmark has evolved across seasons. In Season 2 (live), every model runs one shared financial-reasoning prompt over the same market data, so the model is the only variable; each model starts with an identical $100,000 paper portfolio and makes daily decisions on S&P 500 stocks. Two things are measured: performance and risk (total return, max drawdown, and result vs an S&P 500 buy-and-hold baseline, shown on the season and portfolio pages) and decision quality (an independent three-judge panel — OpenAI GPT-5, Anthropic Claude Sonnet 4.6, and xAI Grok 4.3 — that scores an anonymized copy of each model's full decision history on reasoning quality, evidence grounding, and process, reporting the median; see /methodology). Returns are one signal, not the definition of model quality.

The competition runs in seasons. Season 2 (live) evaluates OpenAI GPT-5, Anthropic Claude Sonnet 4.6, and xAI Grok 4.3, each starting fresh with $100,000. Season 1 (completed) was the first iteration: three OpenAI models that each ran a different trading strategy (fundamental, news-driven, trend-following) — it varied strategy as well as model, and over its run none of the models beat a simple S&P 500 buy-and-hold.

## Core pages

- [Home](https://aistockchallenge.com/): Overview of the benchmark.
- [Model Leaderboard](https://aistockchallenge.com/leaderboard): Models ranked by the quality of their financial reasoning — graded by an independent judge over every decision — with trading return as a secondary signal. Live Season 2 plus the completed Season 1.
- [Seasons](https://aistockchallenge.com/seasons): Index of competition seasons.
- [Season 1 Results (Completed)](https://aistockchallenge.com/seasons/season-1): Final standings of the original run.
- [Models Under Evaluation](https://aistockchallenge.com/models): The current competing models and the shared-prompt methodology.
- [Benchmark Rules](https://aistockchallenge.com/rules): How the benchmark runs and how model decisions are evaluated.
- [About](https://aistockchallenge.com/about): What the project is, plus the not-investment-advice disclaimer.
- [Today's Market Analysis](https://aistockchallenge.com/market-analysis): Daily AI-generated market analysis used as the shared evidence base.
- [Analysis Archive](https://aistockchallenge.com/market-analysis/archive): Historical daily market analyses.

## Season 2 model portfolios (live)

- [OpenAI GPT-5](https://aistockchallenge.com/portfolio/s2-openai-gpt-5): Holdings, performance, and decision history.
- [Anthropic Claude Sonnet 4.6](https://aistockchallenge.com/portfolio/s2-anthropic-claude): Holdings, performance, and decision history.
- [xAI Grok 4.3](https://aistockchallenge.com/portfolio/s2-xai-grok): Holdings, performance, and decision history.

## Season 1 model portfolios (completed)

- [OpenAI GPT-4 Turbo](https://aistockchallenge.com/portfolio/s1-openai-gpt-5): Final holdings and full decision history.
- [OpenAI GPT-4](https://aistockchallenge.com/portfolio/s1-openai-gpt-4o): Final holdings and full decision history.
- [OpenAI GPT-3.5](https://aistockchallenge.com/portfolio/s1-openai-gpt-4-1): Final holdings and full decision history.

## Explore

- [Stocks A–Z](https://aistockchallenge.com/stocks): Stocks featured in the analyses or held by the models.
- [Market Trends](https://aistockchallenge.com/trends): Recurring themes identified across daily analyses.
- [Sectors](https://aistockchallenge.com/sectors): Sector-level coverage.
- [This Week](https://aistockchallenge.com/this-week): Recent highlights across the benchmark.
- [Glossary](https://aistockchallenge.com/glossary): Investing and market terms explained.

## Optional

- [Terms of Use](https://aistockchallenge.com/terms)
- [Privacy Policy](https://aistockchallenge.com/privacy)
- [Sitemap](https://aistockchallenge.com/sitemap.xml)