Brushing teeth = 20,000 AI prompts
Brushing teeth equals roughly 20,000 AI prompts on the water side: 6,000 mL, while an average text prompt weighs just 0.3 mL. The math, the source and detailed equivalents are right below, with public, verifiable numbers.
Figures updated on June 30, 2026 · Source : US EPA WaterSense : usages domestiques de l'eau
The water of a prompt is what evaporates to cool the data center while it answers. For food and goods we count virtual water: all the water mobilised by production, not just what comes out of the tap. Both compare as orders of magnitude, which is exactly what this page shows.
Why 20,000 prompts?
The math fits in three lines, using public, sourced values:
- 1.Brushing teeth: 6,000 mL (US EPA WaterSense : usages domestiques de l'eau)
- 2.1 text prompt: 0.3 mL (published range: 0.26 to 0.32 mL)
- 3.6,000 mL ÷ 0.3 mL ≈ 20,000 prompts
In other words, “Brushing teeth” weighs as much as 20,000 questions asked to a generative AI. It is an order of magnitude, not a to-the-decimal measurement: sources publish ranges, and we use a median value, explained in our methodology.
What about a generated image or a reasoning prompt?
Not every AI use weighs the same. A generated image costs about 9 mL and a “reasoning” prompt about 20 mL, versus 0.3 mL for a simple text prompt. So “Brushing teeth” is also roughly 667 times one generated image, or 300 times one reasoning prompt.
Convert your own usageWhere do these numbers come from?
The value we use for “Brushing teeth” comes from “US EPA WaterSense : usages domestiques de l'eau”, referenced like all our data on the Sources page. No number on this page is made up: every value can be traced back to a public document.
On the prompt side, Google and OpenAI report between 0.26 and 0.32 mL of direct cooling water per request; we use 0.3 mL. Counting the upstream water of electricity generation, the figure sits closer to 1.5 mL.