Google NotebookLM Adds Deep Research Tool and New File-Type Support in Major 2025 Update

Google NotebookLM Adds Deep Research Tool and Support for More File Types — A Major Upgrade for AI-Powered Workflows

Google has rolled out one of the biggest updates yet to NotebookLM, its AI-powered research and note-taking assistant. With the addition of the new Deep Research tool and expanded support for more document formats, NotebookLM is quickly becoming one of the most capable productivity AIs for students, professionals, analysts, and creators. This update enhances the way users interact with uploaded files, enabling smarter research, deeper analysis, and more flexible workflows across Google’s productivity ecosystem.

The google notebooklm deep research tool support file types update brings several user-requested features: richer file compatibility, more advanced reasoning, better long-form answers, and the ability to analyze complex data across multiple sources in a single project.

📚 What Is the New “Deep Research” Tool in NotebookLM?

Deep Research is an advanced AI mode inside NotebookLM that performs multi-step reasoning across uploaded content. Instead of short, surface-level summaries, the tool dives deeper — analyzing arguments, comparing sections, tracking patterns, extracting insights, and generating well-structured, long-form responses.

• Multi-document reasoning: The AI reads across all uploaded files and connects relevant information.
• Source-cited answers: NotebookLM produces responses linked directly to document excerpts.
• Long-form synthesis: Users can request detailed research summaries, essays, or structured reports.
• Context memory: The Deep Research tool maintains session memory while working through tasks, improving accuracy over time.

For students, journalists, and corporate teams, Deep Research provides a new way to gather insights without manually switching between documents or tools.

🗂️ Expanded File-Type Support — More Flexibility Than Ever

One of the most impactful improvements is the addition of support for more formats, making NotebookLM more versatile for real-world workflows. Earlier versions had limited compatibility. Now, users can upload and analyze a broader range of content types.

• Google Sheets: NotebookLM can read tables, analyze trends, and generate insights directly from spreadsheet data.
• Google Docs: Full support for multi-page documents, collaborative notes, assignments, and reports.
• PDF files: Extraction of text, tables, and citations from research papers, invoices, whitepapers, and scanned documents.
• Text and Markdown: Ideal for developers, researchers, and technical writers.
• Presentations (Slides): AI can summarize decks, extract bullet points, or generate outlines for new presentations.
• Images with text (OCR): NotebookLM can interpret diagrams, screenshots, and images containing readable text.

This expansion means users can now upload materials from multiple sources — companies, clients, classrooms, or external research — and seamlessly connect them within a single NotebookLM project.

🎯 What You Can Do with the New Features

With Deep Research + new file support, NotebookLM becomes more than a productivity assistant — it becomes a comprehensive research engine.

• Create structured reports: Generate long-form explanations, case studies, or market analysis papers.
• Compare documents: Identify differences, similarities, contradictions, and hidden relationships across files.
• Build study guides: Automatically produce chapter summaries, flashcards, and question sets.
• Extract data from spreadsheets: NotebookLM can interpret charts, calculate trends, and summarize findings.
• Plan projects: Create to-do lists, timeline breakdowns, and detailed project documentation.
• Generate citations: Pull accurate references directly from uploaded materials.

💡 Major Improvements in AI Reasoning and Output Quality

NotebookLM’s latest update includes enhancements to reasoning depth and factual consistency. The Deep Research tool is specifically engineered to produce: