Generate PDF Table of Contents
Auto-detect PDF headings and generate a clickable Table of Contents. Free, no signup, browser-based.
About PDF Toc Generator
PDF Table of Contents Generator automatically detects headings in your PDF and creates a clickable, navigable Table of Contents — either as a new first page inserted into the document or as a PDF bookmark tree (outline). The tool scans each page for text formatted as headings (larger font size, bold, positioned at the top of a column), infers heading levels (H1, H2, H3) from font size ratios, and builds a hierarchical outline. All processing runs in your browser via pdf-lib. For PDFs already containing bookmarks, the tool can rebuild or extend the bookmark tree. For PDFs with no structural metadata, it uses font-size heuristics and positional analysis to reconstruct document hierarchy — the same approach used by professional PDF processing software.
Most online tools require you to manually enter every heading title and page number. This tool auto-detects headings from PDF content and builds the TOC for you. Even on complex technical documents with nested H1/H2/H3 structures, the heuristic detection produces a ready-to-review outline that you can edit before embedding — saving hours of manual work on long documents.
How We Compare
Compared to desktop alternatives like Adobe Acrobat Pro (starting at $19.99/month), Smallpdf ($12/month for unlimited), or iLovePDF ($9/month Premium), PDF AI Tools delivers comparable quality at $0 for the core feature set. We skip the subscription friction by processing most operations directly in your browser with WebAssembly — no server infrastructure costs to pass on to users. Our AI features (summarization, chat, OCR) use a pay-as-you-go backend that keeps your total cost well under $5/month even for power users.
How to Use Generate PDF Table of Contents
- Step 1: Upload your PDF
- Step 2: The tool scans the document and shows a detected heading list for review
- Step 3: Edit, add, or remove headings and set levels (H1/H2/H3)
- Step 4: Choose output: TOC page, PDF bookmarks, or both
- Step 5: Click "Generate TOC" and download the updated PDF
Why Choose PDF AI Tools
We've built PDF AI Tools to replace expensive desktop software like Adobe Acrobat for 95% of common document workflows — at zero cost to you. Unlike competitors who gate features behind paywalls, add watermarks, or limit file sizes, our tools are genuinely free and genuinely unlimited. Your privacy matters: files processed client-side in your browser never touch our servers, and even AI-powered features use encrypted, auto-deleting processing pipelines.
Key Features
- Auto-detects headings from font size, weight, and position — no manual entry required
- Multi-level hierarchy: H1, H2, and H3 from font size ratios
- Inserts TOC as a new first page with clickable links to each section
- Adds PDF bookmark tree (outline) for sidebar navigation in all PDF readers
- Editable heading list — review and correct auto-detected headings before generating
- Custom TOC formatting: font, size, dot leaders, right-aligned page numbers
- Handles Roman numeral, alphabetic, and decimal page numbering
- 100% browser-side via pdf-lib — no server processing
Frequently Asked Questions
How does auto-detection work?
The tool measures font sizes across all pages and identifies text that is consistently larger or bolder than body text. Lines meeting the threshold criteria are treated as headings, with the largest as H1, next as H2, etc.
Can I edit the auto-detected headings?
Yes — all detected headings are shown in an editable list before the TOC is generated. You can rename, delete, reorder, or change the heading level of any entry.
Does the TOC page have clickable links?
Yes — each entry links to the corresponding page in the PDF. The bookmark tree also provides sidebar navigation in Adobe Acrobat, Chrome, and all modern PDF readers.
Does it work on scanned PDFs?
Scanned PDFs have no real text, so heading detection is not possible. Run OCR first to create a text layer, then run the TOC generator.