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# ChatGPT Surpasses 400 Mn Weekly Active Users
- URL: https://www.theleftshift.com/chatgpt-surpasses-400-mn-weekly-active-users/
- Published: 2025-02-21T06:41:04.000Z
- Updated: 2025-02-21T06:41:04.000Z
- Description: ChatGPT is being used by about 5% of the world's population today.
- Author: The Left Shift Bureau
- Tags: AI Startups, #a42

ChatGPT has now crossed an impressive 400 million weekly active users (WAU), with over 2 million business users leveraging the tool for work, according to OpenAI’s Chief Operating Officer, Brad Lightcap. 

In a recent post on X, Lightcap shared the company’s excitement about serving 5% of the world every week, highlighting the rapid growth of ChatGPT’s user base.

> chatgpt recently crossed 400M WAU, we feel very fortunate to serve 5% of the world every week  
>  
> 2M+ business users now use chatgpt at work, and reasoning model API use is up 5x since o3 mini launch  
>  
> we'll bring GPT-4.5 and GPT-5 to chat and the API soon, with unlimited GPT-5 for… [https://t.co/7hfyUcIyBW](https://t.co/7hfyUcIyBW?ref=theleftshift.com)
> 
> — Brad Lightcap (@bradlightcap) [February 20, 2025](https://twitter.com/bradlightcap/status/1892579908179882057?ref%5Fsrc=twsrc%5Etfw&ref=theleftshift.com)

Lightcap also revealed a significant milestone: usage of OpenAI’s reasoning model API has increased fivefold since the launch of the o3 mini model. Additionally, more than 2 million business users now rely on ChatGPT to enhance productivity and streamline operations.

## **OpenAI Faces Rising Competition from Global Rivals**

While OpenAI continues to dominate the AI landscape, it faces mounting competition, especially from China’s DeepSeek, which raised concerns in January over its potential to disrupt U.S. AI companies’ profitability and market dominance. 

Additionally, xAI, led by Elon Musk, recently [launched its Grok-3 AI model](https://www.theleftshift.com/elon-musks-xai-releases-latest-foundational-model-grok-3/), which has quickly gained traction. Grok-3 became the No. 1 app on the app store, surpassing both ChatGPT and DeepSeek. 

Independent benchmarks also revealed that Grok-3 outperformed Google Gemini 2 Pro, DeepSeek V3, Claude 3.5 Sonnet, and GPT-4 in multiple tests, such as AIME, GPQA, and LCB.

Meanwhile, Anthropic, another leading AI company, is preparing to launch a new reasoning model that will allocate more computational power to complex queries while efficiently handling simpler tasks, further intensifying competition.

## **Sam Altman Weighs Open-Source Future for OpenAI's Next Project**

OpenAI's chief, [Sam Altman](https://x.com/sama?ref%5Fsrc=twsrc%5Egoogle%7Ctwcamp%5Eserp%7Ctwgr%5Eauthor&ref=theleftshift.com), is also contemplating whether to open-source the company's next AI project. He recently polled users on X, asking for feedback on whether they would prefer an o3-mini-level model, which is small but requires GPUs, or a phone-sized version with optimized performance for broader accessibility.

As the AI landscape continues to evolve, OpenAI remains a dominant force in the industry while navigating fierce competition from both established players and emerging tech firms.