Almonds or data centers: which requires more water? Fact-checking AI executive's claim about ChatGPT

OpenAI CEO Sam Altman claimed in a September 1 podcast that 38,000 ChatGPT queries consume the same amount of water as a single California almond. Altman prefaced his statement by acknowledging the number might be incorrect but close, drawing from his own 2025 blog post on ChatGPT's average water use and a 2019 study on California almond farming.

PolitiFact rated Altman's claim "Mostly False," concluding that his comparison is misleading. The analysis found Altman overstated the water consumed by almond agriculture while using an unconfirmed and disputed low estimate for ChatGPT's water usage. Experts noted that OpenAI has not publicized specific data on its overall water consumption.

According to PolitiFact's findings, the 2019 almond study included rainfall and "grey water" in its 12-liter-per-almond estimate, while direct fresh water consumption is closer to 6 liters (1.5 gallons). Similarly, the total water consumed by a single ChatGPT message is highly variable and difficult to measure, depending on factors like data center location, cooling systems, and energy efficiency. Shaolei Ren, a University of California, Riverside, professor specializing in AI's environmental footprint, highlighted the lack of public information on ChatGPT's operational resources.

Updated estimates, including a September 1 study on ChatGPT's 4o model and Google's Gemini AI models, suggest that a single conversational AI prompt could use between 0.6 and 17 milliliters of water. When considering fresh water usage, a single California almond's water consumption is more accurately equivalent to 1,000 to 10,000 conversational AI prompts, significantly fewer than Altman's figure of 38,000.