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NotebookLM is an AI research assistant tool developed by Google.
Announced in July 2023, it continues to receive regular updates as of April 2026.
Its defining feature is that it reads and responds based solely on the documents you upload.
Unlike general-purpose AI tools such as ChatGPT, it does not draw on information from the entire internet — it answers only based on the sources you specify (PDFs, Google Docs, web pages, etc.).
For example, if you upload 10 pages of class notes, you can ask questions about the content, have it summarized, or listen to it as a podcast-style audio recording.
Because it won't answer questions that go beyond your uploaded materials, you get accurate, trustworthy information.
Everything runs in your browser — no special software installation is required.
It also has full Japanese language support.
Pricing includes a free plan and a paid plan (Google One AI Premium: ¥2,900/month).
Even on the free version, you can ask up to 50 questions per day and generate up to 3 audio summaries per day, which is plenty for students and personal use.
The paid version significantly relaxes these limits, making it viable for serious business use.
NotebookLM offers a range of features to help you understand and make use of your materials. Here are five of its main capabilities.
The core function of NotebookLM is loading your documents and asking the AI questions about them.
You can add up to 50 sources — including PDFs, Word files, Google Docs, slides, and web page URLs — to a single notebook (your workspace).
Ask something like "What are the key points of this document?" or "Tell me more about ○○," and it will answer based solely on the content you've uploaded.
It also shows which part of the source material it referenced for each answer, making verification easy.
Audio Overview is a feature that converts your document's content into a natural two-person conversation in audio form.
It lets you absorb the key points of your materials through a conversation that feels just like listening to a podcast.
As of April 2025, Japanese is now supported, and approximately 10 minutes of audio is automatically generated.
It's perfect for busy people who want to understand complex materials by ear while commuting or doing household chores.
Even the free version allows you to generate up to 3 audio summaries per day.
The Explainer Video feature automatically converts document content into a narrated slideshow video.
In March 2026, a new feature called "Cinematic Video Overview" was added, combining three AIs — Gemini 3 (Google's latest AI), Nano Banana Pro (an image generation AI), and Veo 3 (a video generation AI) — to produce high-quality, immersive videos.
This lets you turn presentation or lecture materials into video in a short amount of time.
The Slide Deck feature automatically generates presentation slides from your documents.
A February 2026 update made it possible to give instructions to edit individual slides, and slides can now be downloaded in PowerPoint format (PPTX).
The Infographic feature condenses the key points of your documents into a single visual image.
In March 2026, 10 new design styles were added, making it possible to create even clearer charts and diagrams.
The Study Guide feature automatically generates practice questions and summaries of key points from your documents for exam preparation.
It's especially useful for students studying for regular tests or certification exams.
The FAQ feature automatically generates anticipated questions and answers based on the content of your documents.
It's also valuable for businesses that want to turn internal manuals or product documentation into FAQ format.
The Timeline feature organizes events mentioned in your documents in chronological order.
NotebookLM can be used by complete beginners with no AI experience in just three steps. Here's a guide to the basics.
First, go to the official NotebookLM website at https://notebooklm.google.com.
You can log in with a Google account (the same account you use for Gmail or YouTube).
If you don't have one, you can create one for free.
Once logged in, you can start using it right away.
No special configuration or registration process is required.
After logging in, click the "Create new notebook" button.
A notebook is your workspace for organizing documents.
You can create up to 100 notebooks (on the free plan).
Once you've named your notebook, click "Add source" to upload your materials.
You can add up to 50 sources per notebook, including PDFs, Google Docs, slides, and web page URLs.
Since you can handle multiple documents at once, you can load an entire semester's worth of class notes or a collection of related work documents all at the same time.
Once your documents are uploaded, simply type a question in the input field at the bottom of the screen and press Enter.
You can ask freely in Japanese — for example, "Summarize this document" or "Explain ○○."
You can ask up to 50 questions per day (on the free plan).
You can also click the "Studio" tab to choose from 9 different generation features, including Audio Overview, Explainer Video, slides, infographics, and study guides.
Select what you want to create and press the "Generate" button — your content will be ready in anywhere from a few seconds to a few minutes.
NotebookLM has both convenient features and points to be aware of. Here's what you should know before you start using it.
NotebookLM is recommended for anyone who needs to read and understand documents. More specifically, it's a great fit for these types of users:
On the other hand, it's not the right tool for people who want to ask general questions without any source material, or for those who want to look up the latest news.
For those purposes, tools like ChatGPT, Gemini, or Perplexity are more appropriate.
NotebookLM is at its most powerful when you want to deeply understand documents you already have.
NotebookLM is Google's AI research assistant that deeply understands your documents and lets you use them in a wide variety of formats.
As of April 2026, it continues to evolve and is used by students, researchers, and business professionals around the world.
Here's a recap of the key points from this article:
NotebookLM is an exceptionally powerful tool, especially for those who want to efficiently work through large volumes of documents or cut down on time spent studying or working. Since you can try it out thoroughly on the free plan, why not visit the official site at https://notebooklm.google.com and let AI help you understand your own documents?
This article is a cross-post from AI Friends.
