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A Gemini prompt uses about five drops of water, Google says

AI prompt energy and water use, as reported by Google, OpenAI and outside researchers, set beside a TV, an LED bulb, a microwave and a web search

A single text prompt to a chatbot now comes with a published cost in electricity and water. The numbers are small enough to need decimal points. Google $GOOGL, OpenAI and independent analysts have each put figures on what one request consumes. The most recent figures land in fractions of a watt-hour for energy and fractions of a milliliter for water.

AI prompt energy and water use matters because the per-prompt number is the unit everything else is built from. Chatbots handle prompts at very large scale. Any estimate of their total footprint starts with what a single exchange consumes. Getting that base figure wrong by a factor of 10 changes the result of every calculation stacked on top of it.

The figures in this list come from two kinds of sources. Some are company disclosures. Google published a technical paper on its Gemini Apps on Aug. 21, 2025. OpenAI chief executive Sam Altman gave figures for ChatGPT in a blog post in June 2025. Others are outside estimates. The research group Epoch AI published one in February 2025. An older and much higher one came from a 2023 analysis by Alex de Vries in the journal Joule.

These numbers do not line up neatly. Google reports a median prompt, while Altman described an average query. The two figures describe different services. Google explained how it measured its number, and Altman published no methodology. Outside estimates depend on assumptions about hardware and the length of a response. For that reason, each figure here keeps its own label. This list does not blend them into a single industry number.

Scope matters too. The figures cover text prompts only. They do not cover generating images or video. A longer prompt or a longer answer uses more energy than a median one.

The comparisons are where the figures become easier to picture. Google set its own number beside a few seconds of television. Altman compared his to an oven and to a high-efficiency light bulb. Older estimates were framed against a Google search, using a figure that traces to a 2009 Google statement. Where this list converts a figure into appliance time, it states the wattage it assumes. The answer shifts with the device.

The 10 entries that follow each take one figure or one comparison. Each explains where the number came from and what it does and does not measure.

Google Gemini text prompt energy: 0.24 watt-hours per median prompt

The median text prompt in Google $GOOGL's Gemini Apps uses 0.24 watt-hours of electricity, according to Google. The company published the figure in a technical paper on Aug. 21, 2025. It is Google's measurement of its own service.

A watt-hour is the energy a one-watt device draws over one hour. On that scale, a median Gemini text prompt needs less than a quarter of a single watt-hour.

The word median shapes how the number should be read. A median marks the middle of the range. Half of all prompts use less energy than it does, and half use more. It is not a ceiling. Google's paper does not say that every Gemini request comes in at 0.24 watt-hours.

A median also responds differently from an average to unusual cases. A handful of very long or demanding prompts can drag an average upward. The same prompts have far less pull on a median. A median depends on where the middle prompt sits, not on how large the extremes are.

The figure applies to Gemini text prompts. It is not a number for every kind of request the service handles.

Google counted more than the processors that generate each reply. The company says its measurement covers the full serving system. That includes machines held idle so they are ready for incoming traffic. It also includes the overhead of running the data center itself. A figure limited to the chips would leave both of those costs out. Including them makes the 0.24 watt-hour figure a measure of what it takes to keep the service running, not only the computation behind one answer.

Google also reported a decline over time. The company said the energy used by its median prompt fell by a factor of 33 over a 12-month period. By Google's account, a median prompt at the start of that period used 33 times as much energy as one at the end. That 33-fold drop is Google's own claim about its own system, not an outside estimate.

Gemini prompt water use: about 0.26 milliliters, or 5 drops

A median text prompt in Google $GOOGL's Gemini Apps uses about 0.26 milliliters of water, according to Google. The company likened that amount to five drops.

The number is Google's measurement of its own service, set out in its technical paper on Gemini Apps. It is a company disclosure, not an outside estimate.

As a median, the figure marks the midpoint of the text prompts Google measured. Half used more water than 0.26 milliliters, and half used less. A median is pulled around less by a small number of unusually long or demanding prompts than an average would be.

Data centers use water mainly to cool the servers that run their computing workloads. A per-prompt water figure is a way of dividing that facility-level use across........

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