PDF Table of Contents Generator
Upload a long PDF without navigation and this tool will detect likely headings by font size, then add a table-of-contents page at the start listing each one with its page number.
Heuristic heading detection: it looks for short lines rendered notably larger than the surrounding body text, and can occasionally miss a real heading or flag something that isn't one, especially on unusually-formatted documents. Review the list below before generating.
Preguntas frecuentes
Does this add real, clickable PDF bookmarks?
No. The PDF library this tool runs on doesn't support creating real PDF outlines/bookmarks (the sidebar navigation tree some PDF viewers show). Instead, it prepends one or more plain table-of-contents pages listing each detected heading with the page number it lands on in the final document - a real, readable table of contents you flip to and read, just not a clickable sidebar entry.
How does it detect headings?
It's heuristic: using the font-size information pdf.js reports for each line of text, it looks for short, standalone lines rendered notably larger than the document's dominant body text size. This works well on typically-formatted reports, papers and manuals, but can miss a real heading or flag something that isn't one, especially on unusually-formatted documents - always review the detected list and uncheck anything wrong before generating.
What if no headings are detected?
The generated table-of-contents page will say so plainly instead of listing anything - this can happen if the document doesn't use a visibly larger font size for its headings, or is formatted in an unusual way this heuristic doesn't recognize.
Can I remove a false-positive heading before generating?
Yes, uncheck any entry in the reviewed list that isn't actually a heading - only checked entries are included in the generated table of contents.
Is my PDF uploaded anywhere?
No, this runs entirely in your browser using pdf.js and pdf-lib. Nothing is sent to a server.