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NotebookLM is a free AI research tool developed by Google.
It was released in the summer of 2023, and in June 2024 it added support for Japanese.
Think of it as a smart assistant that reads through large volumes of materials and documents, summarizes their contents, and answers your questions.
Its defining feature is that it answers using only the materials you upload.
Whereas tools like ChatGPT or Gemini draw on knowledge from the entire internet, NotebookLM tells you only what is written in your documents.
This makes it especially useful when you want to dive deep into specific documents—such as company contracts, school reports, or research materials.
Anyone with a Google account (a Gmail account) can start using it for free.
It supports a wide range of file formats, including PDFs, Word documents, YouTube videos, and websites.
As of April 2026, new features continue to be added, and it is used by students and business professionals around the world.
NotebookLM offers many convenient features that can dramatically cut down the time you spend reading through materials. Here are five of its main features.
This is NotebookLM's most popular feature.
Based on the materials you upload, the AI automatically creates a dialogue-style podcast hosted by two AI speakers.
It explains the content in an engaging, radio-show format, so you can listen while commuting or doing household chores.
As of March 2026, it supports over 80 languages, including natural-sounding Japanese conversation.
This is a new feature added in 2026.
While listening to a podcast, if something catches your attention, you can "raise your hand" to ask a question.
The AI hosts will pause, answer your question, and then continue where they left off.
Rather than just passively listening, you can learn through dialogue—a truly groundbreaking approach.
This feature turns the content of your materials into a video using animations and diagrams.
Google's Gemini 3 (the latest AI) and Veo 3 (a video-generation AI) make hundreds of decisions to produce clear, easy-to-understand visuals.
It's useful when you want to understand content not just through audio, but visually as well.
You can use it to prepare for presentations or review material.
You can ask freely about the materials you've uploaded.
Ask something like "What are the key points of this contract?" or "What is the conclusion of this paper?" and the AI will find the answer within your materials and share it with you.
The free version allows up to 50 questions per day.
Answers always include citations (indicating which page the information came from), which makes them highly reliable.
With the latest 2026 features, you can convert your materials into quizzes, flashcards, mind maps, infographics, slide presentations, and more.
You can choose from 10 design styles (cute, professional, anime-inspired, etc.), and download in PowerPoint format.
Studying and preparing presentations becomes significantly easier.
Even first-time users can get started with NotebookLM in just three steps. Here's a guide to the basics.
First, go to the NotebookLM official website (https://notebooklm.google.com).
Once you log in with your Google account, you can start right away.
There's no app to download—it works entirely in your browser (such as Chrome or Safari).
A smartphone app was also launched in May 2025, so you can use it from an iPhone or Android device as well.
Click the "Create new notebook" button and import your materials.
Supported formats include PDF, Word, text, Markdown, EPUB (e-books), images, audio files, YouTube URLs, website URLs, Google Docs, Google Slides, and Google Sheets.
You can add up to 50 sources per notebook (project).
Once your materials are loaded, try typing a question in the chat box.
You can give instructions freely in Japanese, such as "Summarize the key points" or "Explain this section in more detail."
To listen to an Audio Overview, select "Summarize with audio" from the Studio Panel.
After waiting a few minutes, your podcast-style audio will be ready.
Quizzes and slides can be created the same way, with a single click.
NotebookLM has its convenient aspects as well as things to be aware of. Before you start using it, it's good to know both the pros and cons.
NotebookLM is especially recommended for people who need to read and understand large volumes of materials. Specifically, it's a great fit for people like these:
On the other hand, if you want to ask about the latest news or general questions, ChatGPT or Gemini may be better suited.
NotebookLM truly shines when you want to "deeply understand specific materials."
Choose the tool that best matches how you work.
NotebookLM is a free AI research tool from Google that dramatically improves the efficiency of understanding documents.
As of April 2026, it continues to evolve and is used around the world.
Here's a summary of the key points from this article:
NotebookLM is a powerful tool that can save enormous amounts of time, especially for people who need to read and understand large volumes of materials. Since it's completely free, why not try it out at the official website (https://notebooklm.google.com)?
This article is a cross-post from AI Friends.
