IndexStudio uses large language models to read your book, extract key terms with page references, and organize them into a structured index. The result is a solid first draft that requires human review for best results.
Try it on your documentGet started for free — only pay once you're satisfied
Your PDF is parsed to extract the full text content with page boundaries preserved. Text-searchable PDFs produce the best results.
The AI reads the full document and identifies concepts, themes, people, and topics — not just keywords. It understands that "bank" means different things in finance vs. geography.
Each identified term is linked to the specific pages where it appears. Continuous discussions are grouped into page ranges (e.g., 45-52).
The AI identifies related concepts and creates "see" and "see also" references. For example, linking "machine learning" to "artificial intelligence" and "neural networks."
The generated index is loaded into an interactive editor where you rename terms, merge duplicates, add missing entries, and adjust the hierarchy before exporting.
Honest note: The AI produces a solid first draft, but it requires human review for best results. Expect to spend 30-60 minutes editing terminology, adding niche terms, and refining cross-references.
What the AI generates, and what it looks like after 30 minutes of editing
Artificial intelligence, 12, 34, 56, 78, 90, 112 Data, 15, 23, 45, 67, 89, 101, 134 Machine learning, 34, 56 Neural networks, 45 Privacy, 78, 90 Technology, 12, 34, 56, 78, 90, 112, 134
Artificial intelligence, 12-18 ethics and bias, 90-98 regulatory frameworks, 112-120 see also Machine learning; Neural networks Data governance privacy regulations, 78-85 GDPR compliance, 80-82 see also Privacy Machine learning, 34-45 supervised learning, 36-40 unsupervised learning, 41-45 see also Neural networks Neural networks, 45-56 convolutional (CNN), 48-52 transformer architecture, 53-56 Privacy, 78-90 consent frameworks, 86-89 see also Data governance
The AI provides the raw material — flat term lists with page numbers. Editing adds hierarchy, sub-entries, cross-references, and editorial judgment about what to include.
Trade-offs between AI-assisted and traditional professional indexing
| Aspect | AI (IndexStudio) | Professional indexer |
|---|---|---|
| Speed | 10-15 minutes for a 200-page book | 2-4 weeks for a professional indexer |
| Cost | Credits per project | $500-2,000 per book |
| Consistency | Uniform terminology and formatting throughout | Varies by indexer's attention and fatigue |
| Domain expertise | General knowledge — may miss niche terms | Subject-matter experts available in most fields |
| Nuance & judgment | Good at structure, weaker on editorial judgment | Expert at deciding what deserves inclusion |
| Editing required | 30-60 minutes of review and refinement | Minimal — delivered publication-ready |
Non-fiction books: business, self-help, history, biography, reference
Academic papers and dissertations with structured arguments
Technical manuals and documentation with clear topical structure
Specialized fields (medicine, law) may need more editing for terminology accuracy
Fiction indexing is experimental — character and theme extraction is less reliable
Heavily visual books (art, photography) where concepts aren't in the text
IndexStudio uses Gemini 2.5 Pro for index generation and GPT-4.1 for analysis. Models are selected based on document complexity.
Documents are processed in the cloud. Text extraction uses LlamaIndex, and AI analysis runs through secure API connections. Processing typically takes 10-15 minutes.
Your documents are stored securely in private cloud storage. Files are associated with your account and not shared with other users or used for AI training.
See what the AI generates for your specific content.
Upload a PDFGet started for free — only pay once you're satisfied
Upload a PDF and get a structured index draft in about 15 minutes.
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