With $100 and a dream, one enterprising Redditor turned ChatGPT into a day trader, and the results so far have been pretty remarkable.In a post on r/Dataisbeautiful, the Redditor in question — real name Nathan Smith — described his project as a "6-month experiment to see how a language model performs in picking small, [under-covered] stocks with only a $100 budget."According to a chart shared on Reddit, this literal gamble is already paying off. Using GPT-4o, one of OpenAI's most advanced models, the bot-trader's stock portfolio has increased in value by 25 percent over its first month — though given that Smith only invested $100, that means he's only made $25 so far.What's more, that rise was significantly higher than two "small-cap" stock indexes, the Russell 2000 and XBI — in fact, the S&P 500 is up less than 3 percent over the past month — which suggests that ChatGPT very much picked correctly.Its going viral on Reddit.Somebody let ChatGPT run a $100 live share portfolio, restricted to U.S. micro-cap stocks.Did an LLM really bit the market?.- 4 weeks +23.8%while the Russell 2000 and biotech ETF XBI rose only ~3.9% and 3.5%. Prompt + GitHub posted---… pic.twitter.com/3ev8aZ0OTG— Rohan Paul (@rohanpaul_ai) July 29, 2025To be fair, this is far from the first time someone's attempted such a gambit.Last December, researchers from Germany's Duisburg–Essen University published a paper in the journal Finance Research Letters finding that advanced OpenAI models did indeed seem to select money-making stocks. In an interview with Morningstar in June, meanwhile, University of Florida assistant finance professor Alejandro Lopez-Lira said that over years of simulating stock selection, ChatGPT wasn't all that great."Our results on paper are much more optimistic than what the performance in reality would be with a reasonable investment size," Lopez-Lira told the finance blog.There's also a clear logical issue: if AI really was already better than the average human at picking stocks, then all traders would start using AI, changing the entire dynamics of the market and likely meaning that future trades wouldn't operate under the same logic.Responding to the larger trend, Smith decided, as he explained in a GitHub page documenting the experiment, to undertake the endeavor after seeing gimmicky ads that claimed AI could pick undervalued stocks and make investors mucho dinero."It was obvious it was trying to get me to subscribe to some garbage, so I just rolled my eyes," he wrote. "Then I started wondering, 'How well would that actually work?'"As it turns out, it works quite well — but not without human input.Each day, as Smith's GitHub explains, he provides ChatGPT with trading data about its stock portfolio. Smith also said that he implements a strict "stop-loss" rules, which require a trader — in this case, ChatGPT — to immediately sell when a stock reaches a certain price.Though the experiment's stated purpose is to see whether AI can "manage money without guidance," that obviously hasn't happened just yet. Smith has, per his own acknowledgement, committed to daily homework with the trading data inputs until the end of December. Even if that task only takes a few minutes, it's still very much an example of human intervention into a project that, on its face, was meant to let ChatGPT do its thing.Still, it's a fascinating look into what AI, a bit of muscle grease, and $100 can do on the stock market — at least in an otherwise buoyant financial month. The real question? Whether the bot's portfolio will be up or down by the end of the experiment.More on ChatGPT: OpenAI's ChatGPT Agent Clicks "I Am Not a Robot" Button Without a Wink of IronyThe post Someone Gave ChatGPT $100 and Let Trade Stocks for a Month appeared first on Futurism.