---
title: "Which AI chatbots are the most used?\nThe 2026 ranking"
description: "ChatGPT is still the most used AI, Gemini has nearly doubled its share and companies pay for Claude first. The 2026 ranking, worldwide and in France, and why."
canonical: https://projetcelsius.com/en/blog/most-used-ai/
author: "Guillaume Pakula"
datePublished: 2026-11-04
dateModified: 2026-11-06
language: en
translationOf: https://projetcelsius.com/blog/ia-les-plus-utilisees/
---

# Which AI chatbots are the most used? The 2026 ranking

**Author**: Guillaume Pakula
**Published**: 2026-11-04
**Updated**: 2026-11-06
**Section**: Explained
**Canonical URL**: https://projetcelsius.com/en/blog/most-used-ai/
**French original**: https://projetcelsius.com/blog/ia-les-plus-utilisees/
**Source**: Projet Celsius (https://projetcelsius.com/en/), a climate strategy consultancy of engineers and PhDs based in Paris and Marseille.

> **ChatGPT is still by far the most used AI**, with more than 1.2 billion users a week according to OpenAI and 56% of web traffic to AI assistants in September 2026 according to Similarweb. **Gemini has nearly doubled its share in a year**, and Claude has quadrupled its own, driven by US companies, which pay it [55% of what they spend](https://menlovc.com/perspective/2026-the-state-of-enterprise-ai/) to build AI models into their software, according to Menlo Ventures. In France, 8 users in 10 go through ChatGPT.

## Key takeaways

- ChatGPT is still far ahead, with **1.2 billion users a week** and 56% of web traffic.
- Gemini has nearly doubled its share of web traffic, to **25%**, driven by Android phones.
- In the United States, **43.8% of the companies tracked by Ramp** pay Anthropic, against 40.6% for OpenAI.
- In France, **48% of people aged 12 and over** used generative AI in 2025, mainly for writing.

Measuring the audience of an AI is not straightforward, because each developer counts in its own way: OpenAI counts its users per week, Google per month, and **neither Anthropic nor Mistral AI, the French developer, publishes any user numbers**. This ranking therefore rests first on a measure common to all of them: the share of visits to AI websites worldwide, tracked by the web analytics company Similarweb, excluding phone apps. Developers' own statements and public surveys complete it.

## Which AI chatbots are the most used worldwide?

A handful of assistants account for most use, and they set the habits of hundreds of millions of people. In September 2026, **3 assistants alone make up more than 90% of web traffic** to AI sites: ChatGPT, Gemini and Claude. The others share a few points, and some, such as Meta AI, live mainly inside other apps.

### ChatGPT is still far ahead, but losing ground

OpenAI reports **more than 1.2 billion users a week** in October 2026, 50% more than a year earlier. ChatGPT is still the world's leading AI site, with **56% of visits**, but its share has **fallen by 15 points in a year**, from 72% to 56%, mainly to the benefit of Gemini.

### Gemini has nearly doubled its share, Claude has quadrupled it

Google announced **more than 1 billion monthly users** for the Gemini app on [28 October 2026](https://blog.google/company-news/inside-google/message-ceo/alphabet-earnings-q3-2026/), and its share of visits to AI sites rose from 13.6% to **25%** in a year. Claude did better in proportion: its share quadrupled, **from 2.3% to 9.6%**, although Anthropic publishes no user numbers at all.

### Meta AI and Grok also count people who come across them without looking

Meta reported **more than 1 billion monthly users** for Meta AI in October 2025. That figure counts everyone who used it once in the month, in WhatsApp, Instagram or Messenger, where it is **built in by default**, which inflates the total. Grok's 117 million or so users likewise include people who come across it on X.

### The ChatGPT boycott mostly benefited Claude

On 28 February 2026, OpenAI announced an agreement with the Pentagon, the US defence ministry, a few days after Anthropic had turned one down. The call to leave ChatGPT, dubbed QuitGPT, sent its uninstalls in the United States soaring, **+295% in a single day** according to the app analytics company [Sensor Tower](https://sensortower.com/blog/chatgpt-uninstalls-surge-amidst-deal-with-us-department-of-war). Claude rose to **number 1 on the US App Store**.

The boycott accelerated a rise of Claude that was already under way, with no visible effect on ChatGPT, which has gained **300 million weekly users** since. Our [ranking of the most ethical AI assistants](https://projetcelsius.com/en/blog/most-ethical-ai/) looks at what triggered it.

## A national case: how is AI used in France?

Taken as a national case, France shows generative AI taking hold in 2 years, but not among everyone. **48% of people aged 12 and over** used it in June 2025, the latest figure published, **up from 20% in 2023**, according to the [Digital Barometer](https://www.arcep.fr/uploads/tx_gspublication/barometre-du-numerique-edition-2026_RAPPORT.pdf) (Baromètre du numérique) produced by Crédoc, a French research centre on living conditions, for Arcep, the French electronic communications regulator. The gap between age groups is huge: **85% of 18 to 24-year-olds**, against 15% of people aged 70 and over.

Users often name several tools. ChatGPT is named by **79% of them**, followed by Gemini, named by 31%, ahead of Vibe, the assistant from Mistral AI, at 14%. In time spent, measured in April 2026 by Médiamétrie, the French audience measurement company, for [Arcom](https://www.arcom.fr/se-documenter/etudes-et-donnees/etudes-bilans-et-rapports-de-larcom/barometre-daudience-des-services-dintelligence-artificielle-1ere-edition), the French audiovisual and digital regulator, ChatGPT takes 76% of the time, and **Claude 5%, already ahead of Gemini**.

Use also follows occupation: **77% of self-employed people and 76% of managers and professionals** use generative AI in France, **against 38% of manual workers**, according to Crédoc. Our article on [the impact of AI on jobs](https://projetcelsius.com/en/blog/ai-impact-on-jobs/) puts figures on what this use changes in each occupation.

## Why do people choose each AI?

The ranking does not say why people choose one AI over another. Each assistant has **its own way in**, a habit, a phone, office software or a messaging app, and that explains the ranking better than the quality of the answers, which usage studies do not measure.

### ChatGPT out of habit, Gemini and Copilot because they are already installed

ChatGPT is the default tool. The first to arrive, in November 2022, it gave its name to generative AI, and **its free version is enough for most people**: only 19% of French users pay for a subscription, all tools combined.

Nobody had to go looking for Gemini. Google put it into its search engine, into Android and into its office software. In the United States, **58% of AI users** use it in 2026, up from 36% a year earlier, according to Menlo Ventures, a fund that invests in Anthropic, the developer of Claude. That is **only just below ChatGPT**.

Copilot likewise arrives with Windows, Outlook and Word, in companies that already pay for their Microsoft licences: Microsoft claims **more than 30 million paid licences**. Meta AI turns up in WhatsApp, Instagram and Messenger **without anyone installing it**, and 34% of US AI users use it.

### Claude is chosen for work

Claude's users are more often highly qualified professionals in tech or finance, and **82% pay for a subscription**, according to the same fund. Developers have adopted it for Claude Code, **a tool that writes and fixes code** for them. Claude generates neither images nor video.

### The others bet on search, Europe or being free

Perplexity presents itself as an answer engine that cites its sources, and its share of US AI users **has doubled in a year**, to 16%. Vibe, the former Le Chat from Mistral AI, is named by **22% of 60 to 69-year-olds** in France, which Crédoc links to older people's attachment to products made in France. DeepSeek, which is free, is named by **15% of 12 to 17-year-olds**.

## What do people use AI chatbots for?

What people ask an AI shows what it replaces. In France, AI has taken writing away from the search engine: to write, translate or correct a text, **42% of users** turn to an AI first. To look up information, **55% still go to the search engine first**, according to Crédoc.

On ChatGPT, **73% of messages have nothing to do with work**, according to a study by OpenAI and Harvard economists published in September 2025 on 1.1 million conversations. Practical guidance, information seeking and writing make up most of them, and code **barely 5%**.

Claude leans towards work. According to the Anthropic Economic Index, which Anthropic draws from its own conversations, **93% of conversations produce something**, mainly explanations, documents and advice. Computer and mathematical occupations account for **35%** of them.

In the United States, AI became the default tool for several activities in 2026, according to Menlo Ventures: **61% of people who write** do so with an AI, and 58% of those who code. No independent study yet shows which assistant serves which occupation, apart from developers.

## Which AI do companies use?

**In companies, Claude has become the reference work tool**, while ChatGPT remains the tool of the general public. US companies pay Anthropic, its developer, first, according to 2 sources that measure different things and point in the same direction.

### Anthropic has overtaken OpenAI in business spending

The first counts the companies that pay. Ramp, a payment card company, sees the invoices of 85,000 US companies and draws the [Ramp AI Index](https://ramp.com/data/ai-index) from them: in September 2026, **43.8% of them pay Anthropic**, slightly more than pay OpenAI, whereas Anthropic was below 20% at the end of 2025.

The second counts the money. According to [Menlo Ventures](https://menlovc.com/perspective/2026-the-state-of-enterprise-ai/), a fund that invests in Anthropic, the company receives **55% of the sums** that businesses pay to build an AI model into their own tools, far more than OpenAI. Coming from an investor, this figure should be read **alongside Ramp's**.

### Developers have adopted Claude Code, and French managers have adopted AI

Among developers, the measure is a survey. Of those who use a coding assistant, **66% use Claude Code**, **up from 41% a year earlier**, according to the [2026 annual survey](https://survey.stackoverflow.co/2026/ai) of Stack Overflow, the large programmers' help site.

In France, **50% of managers and professionals** used generative AI at least once a week in March 2026, up from 35% a year earlier, according to [Apec](https://www.banquedesterritoires.fr/sites/default/files/2026-05/210526%20-%20Etude%20Apec%20-%20Cadres%20et%20IA.pdf), the French association for executive employment. Insee, the French national statistics institute, counts **58% of companies with 250 or more employees** using it in 2025. Our article on [a company's digital footprint](https://projetcelsius.com/en/blog/corporate-digital-carbon-footprint/) places AI among the other items.

## How much electricity do these questions use?

An audience of this size has an electricity cost, which is why each of our rankings covers it: the more an AI is used, the more its footprint matters, even when each question weighs little. A quick question uses **about 0.3 Wh** (watt-hour) of energy, as much as an LED bulb lit for 2 minutes, according to Projet Celsius's AI Database, and roughly as much as [a Google search](https://projetcelsius.com/en/blog/chatgpt-vs-google-search-energy/).

Yet ChatGPT was receiving **2.6 billion messages a day** in June 2025, according to OpenAI. Over a year, these messages use **as much electricity as 60,000 French households**.

This calculation counts every message as a simple question: [images](https://projetcelsius.com/en/blog/ai-image-carbon-footprint/), [video](https://projetcelsius.com/en/blog/ai-video-environmental-impact/), [reasoning mode](https://projetcelsius.com/en/blog/reduce-ai-environmental-impact/) and coding agents **multiply the energy used**, and these are the uses that are growing in companies. The detail is in [our article on ChatGPT's energy use](https://projetcelsius.com/en/blog/chatgpt-query-energy-consumption/), the global scale in [AI electricity consumption](https://projetcelsius.com/en/blog/ai-electricity-consumption/), and the trend in [AI by 2030](https://projetcelsius.com/en/blog/ai-environmental-impact-2030-2050/).

> An organisation's footprint depends less on the assistant it chooses than on the number of questions and the heavy tasks it gives it.

## Our verdict

The audience ranking does not tell you which AI to choose, but it does show what each one does best.

> **The verdict** **The ranking is now read by use more than by brand.**
> - **ChatGPT remains the assistant for everyday life**: the best known, free for the most part, and used mainly outside work.
> - **Claude is the assistant for work and code**, the one companies pay for first, even though its audience is still far behind.
> - **Gemini and Copilot win through software that is already installed**, the Android phone or Office, more than through their answers.
> - For an organisation, the useful ranking is that of its own use: **take stock of the tools in service**, personal accounts included, and of the share of heavy tasks, images, video and agents.
> - Read every usage study with its author in mind: Menlo Ventures invests in Anthropic, which publishes the Economic Index, and the study on ChatGPT is co-authored by OpenAI.

The [AI footprint calculator](https://projetcelsius.com/en/tools/ai-carbon-footprint-calculator/) gives a first order of magnitude, and our method for [bringing AI into your Bilan Carbone®](https://projetcelsius.com/en/blog/ai-emissions-carbon-accounting-scope-3/), the French carbon accounting method, makes it possible to track it over time. Our article on [the carbon footprint of AI in your company](https://projetcelsius.com/en/blog/ai-carbon-footprint-in-your-company/) shows what an hour of a coding agent weighs.

## Key takeaways

- ChatGPT is still the most used AI in the world, with **more than 1.2 billion users a week** and 56% of web traffic to AI assistants in September 2026.
- Gemini has **nearly doubled its share of traffic** in a year, to 25%, driven by Android and Google, and Claude has quadrupled its own, to almost 10%.
- US companies pay Anthropic first: **43.8% of the companies tracked by Ramp** pay it in September 2026, and it receives 55% of the sums paid for models according to Menlo Ventures, its investor.
- In France, **48% of people aged 12 and over** use generative AI, 8 users in 10 name ChatGPT, and AI has taken writing away from the search engine.
- Each AI has its own way in: **habit for ChatGPT**, the phone for Gemini, work for Claude, Office for Copilot, messaging apps for Meta AI.

To choose on other criteria, see [our ranking of the most polluting AI assistants](https://projetcelsius.com/en/blog/most-polluting-ai/) and [our ranking of the most ethical AI assistants](https://projetcelsius.com/en/blog/most-ethical-ai/). The [ranking of the best AI of 2026](https://projetcelsius.com/en/blog/best-ai-2026/) brings our 3 rankings together.

## Frequently asked questions

## Frequently asked questions

### What is the most used AI in the world?

ChatGPT, from OpenAI, with more than 1.2 billion users a week according to OpenAI in October 2026 and 56.4% of global web traffic to AI sites in September 2026 according to Similarweb. Google's Gemini comes second, with 1 billion monthly users of its app and 25% of web traffic.

### What is the most used AI in France?

ChatGPT: 79% of French users of generative AI name it among their tools, according to the Digital Barometer by Crédoc, a French research centre (June 2025), and it takes 76% of the time spent on AI services in April 2026, according to Arcom, the French audiovisual and digital regulator. Gemini (31%) and Vibe, from Mistral AI (14%), are the next most named, but in time spent, Claude (5%) is ahead of Gemini (4%).

### Why is ChatGPT the most used AI?

The first to arrive, in November 2022, ChatGPT gave its name to generative AI, and its free version is enough for most people. It mainly serves everyday life: 73% of messages have nothing to do with work, according to a study by OpenAI and Harvard published in September 2025.

### Which AI do companies use most?

US companies pay Anthropic, the developer of Claude, first: 43.8% of Ramp's client companies in September 2026, against 40.6% for OpenAI. According to Menlo Ventures, an investor in Anthropic, Claude also receives 55% of the sums companies pay to build AI models into their software. Microsoft 365 Copilot has more than 30 million paid licences.

### How many people in France use AI?

48% of people aged 12 and over used generative AI in June 2025, up from 20% in 2023, according to the Digital Barometer by Crédoc for Arcep, the French telecoms regulator. 85% of 18 to 24-year-olds use it, against 15% of those aged 70 and over. Médiamétrie, the French audience measurement company, counts 33 million unique visitors to AI services in March 2026.

### How many users does Claude have?

Anthropic publishes no user numbers. Claude accounts for 9.6% of global web traffic to AI sites in September 2026, up from 2.3% a year earlier, according to Similarweb, and about 5% of the time spent on AI in France according to Arcom. In the United States, 20% of AI users use it in 2026, up from 7% in 2025, according to Menlo Ventures.

### Did the ChatGPT boycott work?

Partly. QuitGPT sent ChatGPT uninstalls in the United States soaring (+295% on 28 February 2026, according to Sensor Tower) and took Claude to the top of the App Store. But ChatGPT has gained about 300 million weekly users since: the boycott mainly lifted Claude.

## Sources

- Similarweb, shares of web traffic to generative AI sites, October 2025 to September 2026, published on 12 October 2026 and reported by [OfficeChai](https://officechai.com/ai/geminis-traffic-share-falls-for-fourth-straight-month-as-chatgpt-regains-ground-similarweb-data/)
- Alphabet, [third-quarter 2026 results](https://blog.google/company-news/inside-google/message-ceo/alphabet-earnings-q3-2026/), 28 October 2026
- Menlo Ventures, [2026: The State of Consumer AI](https://menlovc.com/perspective/2026-the-state-of-consumer-ai/), 16 September 2026, Morning Consult survey of 5,067 US adults (Menlo Ventures is an investor in Anthropic)
- Menlo Ventures, [2026: The State of Enterprise AI](https://menlovc.com/perspective/2026-the-state-of-enterprise-ai/), 3 November 2026 (Menlo Ventures is an investor in Anthropic)
- Ramp, [AI Index](https://ramp.com/data/ai-index), September 2026 data, accessed on 5 November 2026
- Anthropic, [Anthropic Economic Index, June 2026 report](https://www.anthropic.com/research/economic-index-june-2026-report), 26 June 2026
- Anthropic, [Anthropic Economic Index, March 2026 report](https://www.anthropic.com/research/economic-index-march-2026-report)
- Aaron Chatterji et al. (OpenAI and Harvard), [How People Use ChatGPT](https://www.nber.org/papers/w34255), NBER Working Paper 34255, September 2025
- Sensor Tower, [ChatGPT uninstalls surge amidst deal with US Department of War](https://sensortower.com/blog/chatgpt-uninstalls-surge-amidst-deal-with-us-department-of-war), March 2026
- Stack Overflow, [Developer Survey 2026, AI](https://survey.stackoverflow.co/2026/ai), 6 October 2026
- a16z, [Top 100 Gen AI Consumer Apps, 7th edition](https://a16z.com/100-gen-ai-apps-7/), 5 October 2026
- Crédoc for Arcep, Arcom, the CGE and the ANCT, [Baromètre du numérique, 2026 edition](https://www.arcep.fr/uploads/tx_gspublication/barometre-du-numerique-edition-2026_RAPPORT.pdf) (in French), charts 4 and 5, fieldwork in June 2025
- Arcom and Médiamétrie, [Baromètre d'audience des services d'intelligence artificielle, 1st edition](https://www.arcom.fr/se-documenter/etudes-et-donnees/etudes-bilans-et-rapports-de-larcom/barometre-daudience-des-services-dintelligence-artificielle-1ere-edition) (in French), 16 June 2026
- Reuters Institute, Generative AI and News Report 2025, October 2025
- Insee, [Insee Première No. 2120](https://www.insee.fr/fr/statistiques/9025878) (in French), 21 July 2026
- Apec, [Cadres et IA](https://www.banquedesterritoires.fr/sites/default/files/2026-05/210526%20-%20Etude%20Apec%20-%20Cadres%20et%20IA.pdf) (in French), May 2026
- Projet Celsius, AI Database (Base IA): quick question 0.3 Wh, global electricity 458 gCO2e/kWh (Ember), November 2026; for ChatGPT messages, about 290 million kWh and 130,000 tCO2e a year
- QuestMobile, via TechNode, monthly users of AI apps in China, May 2026
- Fortune, Microsoft Copilot, 21 May 2026, and Microsoft, results of 29 July and 28 October 2026
- Microsoft Research, [Working with AI](https://arxiv.org/abs/2507.07935), arXiv 2507.07935