Gemini 3.0 is set to roll out any day now. Some might already be using it since Gemini tends to quietly roll out features. But until it’s officially in my model picker, I’m going to continue enjoying Gemini 2.5 Flash. Often associated with Nano Banana for image generation and image editing, the smart model has an overlooked feature that some may not be aware of — Deep Thinking.
If you’re wondering why you would need Deep Thinking, you’re not alone. Many users often feel this feature should be reserved for mathematicians or researchers with major projects or questions that need deeper solutions.
But here’s the thing, if you like Flash 2.5 for Nano Banana, you’re going to love Flash 2.5 Deep Thinking for fact checking and writing. The model reasons before it reacts, and, when paired with Search Grounding, it’s the secret to getting the most accurate, verified answers.
What is Search Grounding?
Search Grounding means that Gemini doesn’t just generate answers the way we are accustomed to seeing from other chatbots. Instead, it verifies them against live, real-time web data from Google Search before responding.
Instead of relying only on its pre-training (which might be months old), Gemini actively sends queries to the web, reads multiple sources and uses that information to ground its response in current, verifiable facts.
That means when you ask Gemini a fact-based question (“When does the next Windows 11 update roll out?”), it:
- Generates a few internal hypotheses.
- Performs a targeted Google Search in the background.
- Reads the top-ranked pages (often from reliable outlets).
- Cross-checks what it found against its internal knowledge.
- Writes an answer that combines both — and often cites the pages it used.
The good news is, if you're using Gemini on the web, you don't need to do anything to turn on Search Groundling. It's the default for Gemini when it searches for live information. You'll know it's on when you see "sources" tagged beneath the response. You can click on them to view the sites Gemini references.
If you're using Gemini on Android, you may need to go to Settings and enable "Use Google Search results in answers." This gives Gemini permission to ground responses in live search data.
When paired with Gemini’s Deep Thinking mode, you’ll get the best results because Gemini pulls live facts from the web instead of guessing from memory or what it's been trained on.
So, yes, you can fact check using AI, even though it sounds contradictory at a time when chatbots aren't always accurate and AI Overviews are questionable.
Why it matters
When I tell people I use AI for fact-checking I often get questionable looks. And while there's a ton of AI slop out there, tools like Gemini 2.5 Flash can help get the search results you need. With Deep Thinking and responses grounded in accuracy, you'll discover reduced hallucinations. Transparency from sources and credibility when it matters.
This system is how Google hopes to make generative AI trustworthy. While there's a long way to go, aligning Gemini’s outputs with the same real-time information that powers Google Search is a start.
When Deep Thinking is enabled, Gemini doesn’t rush to answer. Instead, it pauses for a few extra seconds to weigh evidence, evaluate multiple sources and trace its reasoning.
You’ll sometimes see a small “thinking” indicator before the response appears and that delay means the model is running through internal logic chains, much like a human double-checking their work before hitting send.
Bottom line
Gemini’s Deep Thinking mode won’t replace your own judgment, but it finally gives users a tool that values truth over speed. When paired with Search Grounding, it's a game changer for getting the most accurate answers in real-time.
So when you want to take a break from generating all those amazing images with the same model, I encourage you to make the most of your Gemini app and try Deep Thinking. Let me know how it goes and drop your feedback about this feature in the comments.
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