Tools

How much energy does an AI query use?

Method

Pick a published figure, set how often you use AI, and see what it adds up to, with the source and scope of every number.

Energy per query
0.34 Wh
provider disclosure · 2025-06
Per day (20 uses)
6.8 Wh
≈ 0.8 h of a 9 W LED bulb
Per year
2.5 kWh
vs a web search
1.1×
search = 0.3 Wh (Official Google Blog)

Is that a lot? At 20 uses a day, a year of this adds up to 2.5 kWh: as much electricity as an average US home uses in 2 hours, or an average EU home uses in 6 hours. One person's prompts are small; the electricity adds up in the buildings that answer everyone's.

Same provider, water: 0.32 mL per query (2.3 L/year at your usage).

Scope of this figure: Not specified by OpenAI (model, boundary and query type undisclosed). Stated by CEO Sam Altman in a blog post, without methodology; compared to 'what an oven would use in a little over one second, or a high-efficiency lightbulb would use in a couple of minutes'. Source: Sam Altman (OpenAI CEO) blog

Where does this energy go?

What is a data center?

A building full of computers (servers) that store data and run online services: websites, video, payments, AI. The machines draw a lot of electricity and give it back as heat that has to be removed, which is why where one is built matters for the power grid, for water and for the neighbours. All the terms used here →

Close-up of rows of server cooling fans next to coolant pipes
Inside: fans and pipes carry the servers' heat away. Photo: Winston Chen, Unsplash.
Rows of large fans on the roof of a data center
Outside: cooling units on a roof in Mesa, Arizona. Photo: Rsparks3, Wikimedia Commons, CC0.
See all 18 published figures and the reference points

Estimates differ by an order of magnitude because they measure different things: model size, prompt length, what hardware and overheads are counted, and the year. Compare scopes, not just numbers.

WhoWhatValueKindDateSource
GoogleGemini Apps (median text prompt)0.24 Wh/promptprovider disclosure2025-08Google Cloud Blog
GoogleGemini Apps (median text prompt)0.03 gCO2e/promptprovider disclosure2025-08Google Cloud Blog
GoogleGemini Apps (median text prompt)0.26 mL/promptprovider disclosure2025-08Google Cloud Blog
GoogleGemini Apps (median text prompt), narrower active-accelerator-only boundary0.1 Wh/promptprovider disclosure2025-08Google Cloud Blog
OpenAIChatGPT (average query)0.34 Wh/queryprovider disclosure2025-06Sam Altman (OpenAI CEO) blog
OpenAIChatGPT (average query)0.32 mL/queryprovider disclosure2025-06Sam Altman (OpenAI CEO) blog
Mistral AILe Chat (Mistral Large 2), 400-token response1.14 gCO2e/responseprovider disclosure2025-07Mistral AI
Mistral AILe Chat (Mistral Large 2), 400-token response45 mL/responseprovider disclosure2025-07Mistral AI
Epoch AIChatGPT (GPT-4o, typical query, ~500 output tokens)0.3 Wh/queryindependent estimate2025-02Epoch AI
International Energy AgencyChatGPT (average request)2.9 Wh/requestagency2024-01International Energy Agency
Microsoft ResearchFrontier-scale LLM (>200B params) on H100 nodes, median query0.31 Wh/queryindependent estimate2025-09arXiv (Microsoft)
Microsoft ResearchFrontier-scale LLM, long reasoning (test-time scaling, ~15x longer queries), median3.91 Wh/queryindependent estimate2025-09arXiv (Microsoft)
MIT Technology Review / University of Michigan ML.EnergyLlama 3.1 8B, one text response0.032 Wh/responseindependent estimate2025-05MIT Technology Review
MIT Technology Review / University of Michigan ML.EnergyLlama 3.1 405B, one text response1.86 Wh/responseindependent estimate2025-05MIT Technology Review
MIT Technology Review / University of Michigan ML.EnergyStable Diffusion 3 Medium, one standard-quality image0.63 Wh/imageindependent estimate2025-05MIT Technology Review
MIT Technology Review / University of Michigan ML.EnergyCogVideoX (newer, higher-quality version), one 5-second video944 Wh/videoindependent estimate2025-05MIT Technology Review
Jegham et al.Short LLM query (benchmark example)0.42 Wh/queryindependent estimate2025-11arXiv
Jegham et al.Most energy-intensive models, long prompt29 Wh/promptindependent estimate2025-11arXiv

Reference points

Questions

How much energy does one AI prompt use?

Published figures for a typical text prompt range from about 0.24 Wh (Google Gemini, median, 2025-08) and 0.34 Wh (OpenAI ChatGPT, 2025-06) to several Wh for long reasoning queries or large open models. Image and video generation use far more.

Why do estimates differ so much?

They count different things: model size, prompt and answer length, which hardware and data-center overheads are included, and when the measurement was made.