Has AI Started 'Deep Thinking'? A Complete Guide to Google Gemini's New 'Deep Think' Mode

Imagine you are grappling with a very difficult math problem or a complex business strategy. When you ask a friend nearby, would you prefer they throw out any random answer in 0.1 seconds? Or would you rather they close their eyes for a moment, say, “Wait, give me a second to think,” and then provide a highly sophisticated and logical solution 10 seconds later?

In most situations, we would choose the latter. This is exactly the core of the new ‘Deep Think’ mode that Google has introduced to the Gemini app. While AI until now has focused on delivering answers ‘faster than anyone else,’ it has now begun to learn how to think for itself—focusing on being ‘much smarter, even if it’s a bit slower.’

Why is this important?

The chatbots we have used so far were actually geniuses at instantly finding ‘the word most likely to come next.’ However, in tasks requiring ‘step-by-step logic,’ such as math problems, scientific arguments, or fixing complex programming errors, they often exhibited ‘hallucinations’—providing nonsensical answers.

Deep Think is an Advanced Reasoning Mode designed to overcome these limitations. [Source 11] This mode goes beyond simple information delivery; the AI undergoes a process of analyzing problems from multiple angles and finding the best answer itself. In simple terms, instead of just spitting out a result, the AI rigorously verifies ‘why this answer came out’ internally. This means AI has begun to more closely mimic the human ‘thought process,’ signaling major changes particularly in the fields of science, research, and engineering. [Source 8]

Easy Understanding: How Deep Think Works

Let’s look at how Deep Think works through two analogies.

1. The Race Between the Tortoise and the Hare

If existing AI models are ‘hares’ that arrive at the finish line at high speeds, Deep Think can be compared to a ‘tortoise’ that steps carefully one step at a time. However, this tortoise isn’t just slow; it meticulously reviews all paths to see if there are traps along the way or if there is a faster shortcut. Google explains this as “using additional ‘Thinking Time’ to solve complex problems.” [Source 11]

2. Navigation That Takes Multiple Roads Simultaneously

By analogy, Deep Think is like a high-performance navigation system that simulates ‘Route A,’ ‘Route B,’ and ‘Route C’ to a destination simultaneously. Instead of chasing just one correct answer, it explores multiple solution paths in parallel. [Source 11] [Source 13] In this process, the AI can correct its own logical errors or find more creative alternatives that weren’t initially considered.

Thanks to these powerful capabilities, the Gemini 2.5 Deep Think model even achieved a gold medal standard score at the International Mathematical Olympiad (IMO). [Source 3] Beyond mere memorization or calculation, AI has reached the level of human geniuses in the realm of advanced logical thinking, where even the world’s smartest high school students struggle.

Current Status: Who can use it and how?

Deep Think is not currently a feature open to all users. Google is primarily providing this feature to subscribers of its highest-tier service, ‘Google AI Ultra.’ [Source 2] The cost of this subscription service is known to be about $250 per month, which includes benefits such as being among the first to use the most advanced AI tools. [Source 13] [Source 7]

If you are an Ultra subscriber, you can experience Deep Think in the Gemini app for Android in the following way:

1. Launch the Gemini App: Open the app on your smartphone.
2. Select Model: Select Gemini 3 Pro from the model selector at the top. [Source 6] [Source 9]
3. Activate Deep Think: Turn on the ‘Deep Think’ option located in the bottom prompt bar. [Source 5]
4. Ask a Question: Now you can enter complex math problems or content requiring analysis.

Google defines this feature as a “deliberate experiment that is slower to respond but provides richer reasoning.” [Source 6] Therefore, its true value is revealed when you ask in-depth questions like “analyze the root cause of this coding error and suggest three solutions” rather than light questions like “what’s the weather today?”

What lies ahead?

The emergence of Deep Think shows that the AI paradigm is completely shifting from ‘fast response’ to ‘sophisticated reasoning.’ Google has already released this model not only as an app but also in the form of an API (a tool that integrates with other applications). This allows selected researchers, engineers, and companies worldwide to receive help in solving complex scientific challenges, such as cancer treatment research or the development of new energy sources. [Source 8] [Source 17]

First unveiled at the Google I/O event in May 2025, it was released based on Gemini 2.5 in August, and is currently operating actively up to the even more advanced Gemini 3 version. [Source 13] [Source 8] Google expressed confidence that “Deep Think pushes the frontier of thinking.” [Source 14]

Now, AI is evolving beyond a secretary that simply performs the tasks we assign, into an ‘intellectual partner’ that works with us to solve difficult problems. Next time you have a very difficult worry, why not say to Gemini, “I’ll give you a moment to think,” and turn on Deep Think mode? That short time when the AI closes its eyes and ‘contemplates’ might become the decisive key to solving your problem.

AI’s Take

MindTickleBytes AI Reporter’s View: Deep Think shows that AI has moved beyond a game of simply guessing the ‘sentence most likely to be the correct answer’ and entered a ‘stage of thought’ where it verifies logical validity itself. The few seconds we wait for an AI’s response are not mere loading times, but times for an ‘intellectual journey’ where the AI explores tens of thousands of paths to solve humanity’s challenges. This change will once again remind us of the value of the ‘process of finding the answer’ over the ‘correct answer’ itself in all fields, including education, research, and business.

References

1. Gemini 2.5: Deep Think is now rolling out - The Keyword
2. Deep Think is available now in the Google Gemini App
3. Google DeepMind: Try Deep Think in the Gemini app
4. Deep Think is now available on the Gemini app for Android
5. Gemini 3 Deep Think is now live for Ultra subscribers inside the Gemini app

6. [Try Deep Think in the Gemini app

   AIC - aicommission.org](https://aicommission.org/2025/08/try-deep-think-in-the-gemini-app/)

7. Gemini 3 Deep Think: Advancing science, research and engineering
8. Gemini 3 Deep Think is now available in the Gemini app.
9. Gemini Deep Think Explained: Google’s Next Step in AI Reasoning
10. Google rolls out Gemini Deep Think AI, a reasoning model that …
11. Gemini 2.5 Deep Think rolling out now for Google AI Ultra
12. Gemini 2.5 Deep Think explained: Everything you need to know
13. Google rolls out powerful creative problem-solving AI model …

FACT-CHECK SUMMARY

• Claims checked: 19
• Claims verified: 19
• Verdict: PASS