While ChatGPT and Gemini compete for users, Grok has quietly gained something even more valuable—our time. According to new data from Similarweb released this December, Grok has led in Average Visit Time for the second month in a row (October and November 2025). This shows a preference for quality over quantity, and it’s starting to worry the big tech companies.
To understand why this matters, consider the difference between the number of users who visit a site and the time they stay. ChatGPT is the most popular AI platform, attracting over 6 billion visits each month. In contrast, Grok captures about 3% of that market. However, once people use Grok, they tend to stay longer.
Here’s the “Stickiness” Leaderboard for November 2025:
- Grok: ~8 minutes per session
- Claude: ~7.5 minutes per session
- ChatGPT: ~6 minutes per session
- Gemini: ~5 minutes per session
For the second month in a row, Grok users spend 33% more time on the site than ChatGPT users. In the digital world, “Time on Site” is the best measure of usefulness. People aren’t just visiting for quick answers; they are engaging in more in-depth work.
Why Are We Staying?
What keeps us interested in Elon Musk’s xAI? It’s not just his bold personality anymore. Three major changes in late 2025 have made Grok a “productivity magnet.”
1. The “Think Mode” & “Big Brain” Logic
Grok-4, released in July 2025, introduced Think Mode. When this is turned on, Grok doesn’t just guess the next word. It pauses to think through different reasoning paths, similar to how a human expert might. This keeps developers and researchers on the platform longer, as they see the AI explain its thought process in real time.
2. DeepSearch & The “X” Pulse
This is Grok’s unfair advantage. While ChatGPT uses Bing, Gemini uses Google Search, and Grok connects directly to X (formerly Twitter). If a major event happens, Grok gets the data within 15 seconds. The DeepSearch feature lets Grok index the web and the many live conversations on X. This helps users who want to know why something is trending or what people are saying about a new law, providing insights that other AIs can’t.
3. The “Unfiltered” Factor
Grok has gained a large following, especially among Gen Z and young professionals aged 25–34, because of its “rebellious streak.” By not using strong “safety filters” that prevent other AIs like Gemini or ChatGPT from answering tricky questions, Grok enables more natural conversations. Users report spending less time debating with the AI’s rules and more time getting the answers they need.
The Infrastructure: Powered by “Colossus”
You can’t achieve this level of engagement without strong support. Grok’s performance boost in late 2025 comes from the Colossus supercluster, which is the most extensive AI training system in the world, located in Memphis. This lets Grok manage a 2-million-token context window, meaning you can upload several entire books, and Grok will remember everything during your 15-minute session.
Technical Definitions
- Average Visit Time: The total time users spend on a site divided by the number of visits. It helps measure “user interest.
- Test-Time Computing: This method gives the AI more processing time to think deeply about complex problems when generating answers.
- Context Window: This refers to how much information an AI can remember at once. Grok’s 2M window is among the highest available.
The Verdict
Recent data show that the AI market is splitting into two segments. Google Gemini is leading in quick questions while browsing. ChatGPT is popular for general use.
However, Grok has carved out a successful niche as the “Deep Work” partner. If you’re a heavy user looking for real-time data and enjoy a bit of sarcasm, you might be part of the reason Grok is at the top of the engagement charts.
