# Using Deep Research in Gemini Notebook (formerly NotebookLM)
> Learn how to use NotebookLM Deep Research in Gemini Notebook: 6 steps, Fast vs Deep Research, how limits work, the Gemini app version and source checks.
By Juli · Published Oct 26, 2026 · https://www.kortex-notebooklm.com/blog/gemini-notebook-deep-research
Big question, empty notebook. That used to mean an afternoon of searching, skimming and bookmarking. Deep Research in Gemini Notebook (formerly NotebookLM) does the first pass for you. Specifically, it plans a search, reads widely and hands back a report plus the sources behind it. It's quick to start and, unfortunately, easy to over-trust. Here's how to run it and what each plan allows. You'll also see how it differs from the Gemini app's version, and how to check what it brings back.
> **Key Takeaways**
> - Deep Research browses hundreds of websites per question ([Google](https://blog.google/innovation-and-ai/models-and-research/google-labs/notebooklm-deep-research-file-types/), 2025).
> - You import the report and choose which sources to keep.
> - Usage refreshes every five hours up to a weekly cap; Pro gets 4x standard usage.
> - Check uncited sources before trusting the report.
## What does Deep Research do in Gemini Notebook?
**Deep Research** is a researcher on call. It takes your question, writes a research plan and browses hundreds of websites, refining the search as it learns (Google, 2025). You get a source-grounded report and a list of sources, and you can import both. Additionally, it all runs in the background while you work. That's the difference from a chatbot answer, because the output isn't a reply you copy somewhere. Instead, it's material that joins your notebook, so every later chat, report or Audio Overview is grounded in it. Judging by search data, people are curious and a little wary. When we analyzed 1,451 Google autocomplete suggestions in October 2026, we found 18 distinct Deep Research searches, ranging from "notebooklm deep research limit" to "notebooklm deep research disappointment".
### Fast Research vs Deep Research: what's the difference?
Both live in the Sources panel. Google describes Fast Research as "best for a quick search" and Deep Research as "best for a full briefing" (Google, 2025). In practice, Fast Research pulls supported sources from the web or from Google Drive files you can access, while Deep Research is an agentic feature that browses up to hundreds of websites for you ([Gemini Notebook Help](https://support.google.com/gemininotebook/answer/16215270?hl=en), 2026). One hands-on test shows the gap:
| | Fast Research | Deep Research |
|---|---|---|
| Searches | The web or your Google Drive | The web. |
| You get | A list of results to import | A report plus every relevant source, cited and not cited. |
| In one test | 10 sources in a few seconds | 35 sources and a report within 10 minutes. |
The test figures come from Android Police, where the Deep Research report cited 19 of its 35 sources ([Android Police](https://www.androidpolice.com/i-tested-notebooklms-deep-research-tool/), 2025). Need a few links fast? Fast Research. Starting a topic from zero? Deep Research.
Fast Research is, in addition, the one your AI assistant can drive. **Kortex MCP** is a connector that lets Claude or ChatGPT work with your notebooks, and it's included with Kortex Pro and Lifetime. With it, Claude can [run Fast Research, import the hits and turn them into an Audio Overview](/blog/gemini-notebook-ai-workflows), then save those steps as a workflow you rerun by name.
## How do you use Deep Research in Gemini Notebook?
Start it from the Sources panel on the web. Type a research question, switch on Web and Deep Research, and search. Results may take a couple of minutes; meanwhile, you can keep working. The feature is only available to users over 18 (Gemini Notebook Help, 2026). Here are the six steps:
1. **Open a notebook** at notebook.google.com and find the Sources panel.
2. **Type a research question** in the search box.
3. **Toggle on Web and Deep Research,** then search.
4. **Review the results.** Import everything, or select View to see the report and every relevant source, cited and not cited.
5. **Pick what to keep.** Select or deselect sources, then import.
6. **Close it.** Cancel or minimize to leave Deep Research mode. Anything you didn't import is discarded.
Write the question like a brief, not a keyword, for instance by naming a time frame. "Remote work productivity" is only a topic. In contrast, "What have studies since 2020 found about remote work in software teams?" gives the search a scope, a time frame and a group. Importantly, the mobile app's help page only describes Fast Research, so run Deep Research on the web.
There's also a second route. Gemini Notebook's agentic chat can complete research inside the conversation, then let you select and import the report and sources ([Gemini Notebook Help](https://support.google.com/gemininotebook/answer/16179559?hl=en), 2026). Google lists that chat on the web for Google AI Ultra subscribers and Workspace business customers with AI Expanded Access. In side-by-side tests, it scored a 78.2% win rate against the old system on web research and source discovery, which Google defines as the ability to discover, retrieve and synthesize sources from the web ([Google](https://blog.google/innovation-and-ai/products/notebooklm/better-research-notebooklm/), 2026). However, Google calls the chat's agentic functions experimental and in early development, so check its work the same way. As a result, either route can leave you with dozens of new sources to sort.
Sort what Deep Research brings back
Kortex shows every source across your notebooks in one table you can filter by notebook, tag or highlight colour, file into folders and download. Free on Chrome.
Add Kortex to Chrome, freeSee the sources table
## What is the Deep Research limit on each plan?
Google doesn't publish a Deep Research count. Instead, Gemini Notebook uses compute-based limits that refresh every five hours until you reach a weekly cap, and paid plans get a multiple of standard usage ([Gemini Notebook Help](https://support.google.com/gemininotebook/answer/17670842?hl=en), 2026). What Google's plan table does fix is the source cap per notebook ([Gemini Notebook Help](https://support.google.com/gemininotebook/answer/16213268?hl=en), 2026). Here's the full table:
| Plan | Sources per notebook | Usage |
|---|---|---|
| Free (Standard) | 50 | Standard. |
| Plus | 100 | 2x standard. |
| Pro | 300 | 4x standard. |
| Ultra (20TB) | 500 | 5x or 20x Pro, by subscription. |
| Ultra (30TB) | 600 | 5x or 20x Pro, by subscription. |
Run the numbers and the tighter limit is often sources, not runs. Import all 35 sources from that Android Police test and you've filled 70% of a free notebook in one go. Usage depends on the complexity of your prompt and the models and features you use (Gemini Notebook Help, 2026), but Google doesn't say how much of it a Deep Research run takes. Consequently, if you go past your limit, Deep Research results may import only partly. Our guide to [Gemini Notebook usage limits](/blog/gemini-notebook-usage-limits) explains the system, and [Plus vs Pro vs Ultra](/blog/gemini-notebook-plans) compares the plans.
## How is it different from Deep Research in the Gemini app?
The Gemini app writes a report you read, while Gemini Notebook builds a notebook you keep working in. In the Gemini app, for example, Deep Research searches Google by default and lets you edit its plan. A report usually takes about 5 to 10 minutes ([Gemini Apps Help](https://support.google.com/gemini/answer/15719111?hl=en), 2026). In Gemini Notebook, by contrast, the report and sources become notebook sources.
| | Gemini app | Gemini Notebook |
|---|---|---|
| Start from | Deep Research in Gemini's text box | Web and Deep Research in the Sources panel. |
| Searches | Google Search by default, plus Gmail, Drive, files or notebooks you add | The web. |
| Edit the plan | Yes, with Edit plan | Not in Google's documented steps. |
| Typical wait | About 5 to 10 minutes | A couple of minutes, per Google. |
| You get | A report you can export to Docs or turn into an Audio Overview | A report and sources inside your notebook. |
| Age | 18 or over | Over 18. |
The two also connect, in fact. The Gemini app can add your notebooks as a Deep Research source (Gemini Apps Help, 2026), which lets you research against material you've already vetted. Which should you pick? Generally, use the Gemini app for a one-off answer, and Gemini Notebook when the topic will need weeks of follow-up questions. For example, a quick market snapshot suits the Gemini app, while a thesis chapter suits a notebook. People ask this a lot: of the 18 Deep Research searches we found in that autocomplete data, 4 compared Gemini Notebook with Deep Research in Gemini or ChatGPT. Our [Gemini Notebook vs Gemini comparison](/blog/gemini-notebook-vs-gemini) covers the wider split.
## Checking the sources Deep Research imports
Review before you import, not after, because the import screen is where you choose. Deep Research shows its report beside every relevant source, cited and not cited (Gemini Notebook Help, 2026). You choose what goes in, and therefore that list needs a human. In Android Police's test of a UK home-buying question, the uncited sources included US home-buying documents (Android Police, 2025).
Here's a simple rule for the import screen. Cited sources thus earn a spot by default, but only after you've spot-checked a few. Uncited sources, on the other hand, are leads, not evidence, so each one has to justify its slot. Five checks cover it:
1. **Spot-check cited sources.** Open two or three and confirm they say what the report claims.
2. **Vet uncited ones.** Import one only if it's on topic, primary and recent enough.
3. **Read the source guide.** Each source's auto-generated summary helps you check its date and publisher.
4. **Ask for evidence.** In chat, ask "Which source supports each claim in the report?"
5. **Leave room.** Near your source cap? Import fewer sources.
Grounding helps; nevertheless, it isn't a guarantee. A 2025 preprint tested a reporting task across 300 documents. NotebookLM hallucinated in 13% of outputs, against about 40% for ChatGPT and Gemini ([Hagar, Agustianto and Diakopoulos](https://arxiv.org/abs/2509.25498), 2025). The main problem was interpretive overconfidence, not invented facts, such as turning one source's opinion into a general statement. Hence it matters most for literature reviews. We analyzed 776 answers to the Kortex MCP waitlist survey (Sep-Oct 2026), and 20 people asked for help with literature reviews, the kind of job where one misattributed claim does real damage. Our [research workflow guide](/blog/notebooklm-for-research) shows how to structure the notebook afterwards.
Writing the draft in Claude or ChatGPT? With Kortex MCP, included with Kortex Pro and Lifetime, you can [ask the vetted notebook from your assistant and get cited answers](/blog/gemini-notebook-in-claude).
## How does Kortex help you manage Deep Research sources?
A single Deep Research run can, in particular, add dozens of sources. **Kortex** is a free Chrome extension that helps you sort, compare and save them, and we built it for libraries that grow faster than anyone can tidy by hand. Its users have run 200,000+ exports ([Kortex](/), 2026). The free plan includes 10 exports a day, and Pro costs $9.99 a month or $4.92 a month billed yearly ([Kortex pricing](/#pricing), 2026). Five features matter most here:
- **Tag and highlight.** Source tags, highlights and saved views keep the useful sources easy to find.
- **Filter by type.** Show only PDFs, Google Docs, web pages, text or YouTube videos.
- **Compare and merge (Pro).** See which sources two notebooks don't share, then merge them without duplicates.
- **Export the evidence.** Download every source as PDF, Markdown, text or a ZIP.
- **Automate follow-ups (Pro).** Tag a notebook #to-summarize and Auto-Researcher starts a briefing doc and flashcards.
Deep Research fills a notebook fast. Therefore, the real work is keeping it usable.
## Frequently asked questions
### What is Deep Research in Gemini Notebook?
It's a Sources panel feature that turns one research question into a report and a set of web sources. It plans a search, browses hundreds of websites and lets you import the report plus the sources you choose. It runs in the background, so you can keep working.
### Is Deep Research free in Gemini Notebook?
Yes, within your usage limits. Google publishes no Deep Research count: usage is compute-based, refreshing every five hours up to a weekly cap, and Plus gets 2x standard usage, Pro 4x and Ultra 5x or 20x Pro (Gemini Notebook Help, 2026). Past the limit, results may import only partly. You must be over 18.
### How long does Deep Research take in Gemini Notebook?
Google says results may take a couple of minutes, and you can keep using Gemini Notebook while you wait. Bigger questions can take longer. In a 2025 Android Police test, Deep Research finished its report within 10 minutes and listed 35 sources, 19 of them cited.
### What's the difference between Fast Research and Deep Research?
Fast Research is a quick scan of the web or your Google Drive that returns a list of results to import. Deep Research searches the web in depth and adds a written report, plus every relevant source, cited and not cited. Use Fast Research to gather material and Deep Research to brief yourself.
### Can Deep Research in the Gemini app use my notebooks?
Yes. Google's Gemini Apps help says you can add notebooks and files, plus Gmail or Drive, as Deep Research sources, with Google Search included by default. That report stays in the Gemini app, where you can export it to Docs, while Gemini Notebook imports its report and sources straight into your notebook.
### Why is Deep Research not available in Gemini Notebook?
Check 3 things. Deep Research is only available to users over 18. Google's mobile app help describes only Fast Research, so start Deep Research on the web. And if you've passed your usage limits, results may import only partly.
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*Editorial note: fact-checked against the official help pages and docs linked above on October 26, 2026. Spotted something out of date? [Contact us](/support) and we will fix it, or read more [about Kortex](/about).*