← Can I take a shower today?

Sources

Where the numbers in “Can I take a shower today?” come from. They are rough estimates, and companies do not publish exact water use per prompt, video or search. We pick the highest values we could find (a worst-case view), so the real water use is probably lower. Some values come from measurements; others are “assumption based on” a measured value, which means we scaled it, and we say how.

Daily budget: 100 L

The United Nations General Assembly recognized that 50 to 100 liters of water per person per day are needed for basic personal and domestic needs. We use the top of that range.

Water per use

Water is estimated from energy: every value uses 4.19 liters of water per kWh, which includes the water used to make the electricity, not only the water used for cooling. Where there is no direct measurement, we scale from a measured value by how much data the activity uses, and we always round up.

WhatValueBasis
AI prompt50 mLRounded up from academic estimates (about 500 mL per 20–50 prompts). Companies report much less: about 0.25 mL (Google, Gemini) and 0.3 mL (OpenAI).
AI image48 mLA 2023 study measured image models. The least efficient one used 11.49 kWh per 1,000 images (11.5 Wh each), which gives 48 mL. The average model used 2.9 Wh per image (12 mL).
AI video0.39 L per secondAbout 0.94 kWh per 10-second video (an independent estimate for Sora 2) × 4.19 L/kWh. Other estimates are lower: for example, about 90 Wh per video.
Search1.3 mLGoogle reported 0.3 Wh per search (2009). Google’s newer figure for a Gemini prompt is similar (0.24 Wh). × 4.19 L/kWh.
Streaming0.42 L per hourThe IEA estimates 0.077 kWh per hour for streaming Netflix. We round up to 0.1 kWh × 4.19 L/kWh.
Social media0.42 L per hourAssumption based on streaming. Feeds play video but also show photos and text, so the streaming value is an upper limit.
Video calls0.42 L per hourAssumption based on data use. Group video calls use about 0.8–2.5 GB per hour, and HD streaming uses about 3 GB per hour. We use the streaming value as an upper limit.
Shopping0.30 L per hourAssumption based on streaming. Pages full of images use much less data than HD video, so we use about 70% of the streaming value.
Cloud apps & docs0.15 L per hourAssumption based on data use. Documents and drives send little data, but design tools and maps send more. We use 1.5 times the music value. No direct figure exists.
Music0.10 L per hourBased on data use. Music uses 40–150 MB per hour, which is 1–5% of HD video. We use 0.10 L, about 5 times higher than that scaling, to stay on the safe side.
Messaging & email0.10 L per hourAssumption based on data use. These are mostly text, photos and voice notes, which use less data than music. We use the music value as an upper limit.

Why these numbers are high

We count the energy of the whole chain (your device, the network and the data center) as if it all happened in data centers. For streaming, the IEA says data centers use only about 5% of the energy, the network about 23% and your device about 72%.

Links

This extension runs only in your browser and sends nothing anywhere. It never stores what you type. On Luma only, it checks your prompt for the words "image" or "video" on the page, so it can tell which one you asked for. It is not made by or connected to any of the companies or websites it names.