Long PDFs are hard to find your way around without bookmarks. This tool reads the text in your file and finds the lines that look like headings, based on their size, weight and numbering. You get a list of bookmarks you can edit: rename them, put them in order, nest sections under chapters and delete the ones you don't need. Then save the PDF, with a table of contents page at the front if you want one.
How to use PDF Bookmarks and TOC
- Add your PDF. The tool reads it and lists the headings it finds.
- Choose whether to start from the found headings, the bookmarks already in the file, or an empty list.
- Rename, move, nest or remove bookmarks, and fix any page numbers.
- Choose whether to add a contents page, and give it a title.
- Select Save Bookmarks and download the new PDF.
How headings are found
- Size and weight against body text: The tool looks at every line of text and compares its size and weight with the normal body text. Lines that are clearly bigger or bold, fairly short, and not repeated at the top of every page are treated as headings.
- How levels are decided: Numbered headings like 2 or 2.1 take their level from the numbers. Other headings get a level from their size, so the biggest become chapters and smaller ones become sections under them.
- What it works well on: It works well on reports, manuals, books and theses made in a word processor.
- Scanned pages have no text to read, so run OCR PDF on them first.
Editing the bookmark list
- Each row has a title, a page number and a level.
- Moving and nesting: Use the arrow buttons to move a bookmark up or down, or to nest it under the one above. A bookmark can only be one level deeper than the one before it, which is how PDF readers expect it.
- Renaming and repointing: Type in the title box to rename it, and change the number to point it at another page.
- Adding and removing: Add bookmarks for anything the detection missed, like an appendix, and remove running titles or captions it picked up by mistake.
- It's all local until you save: All of this happens in your browser until you save.
The table of contents page
- What gets added: If you tick the option, a contents page is added before the first page. It lists every bookmark with its page number and a dotted line, indented by level, and each line is a link to that page.
- Numbers adjust automatically: Page numbers in the contents and in the bookmarks are adjusted for the pages that were added, so everything still points to the right place.
- Long lists: A long list spreads over more than one contents page.
- Titles in other scripts: The page uses a standard Latin font, so it's only added when every title uses Latin letters. Bookmarks in Arabic, Urdu and other scripts still work in the bookmarks panel.
When people use PDF Bookmarks and TOC
Finishing a thesis or report
Add chapter and section bookmarks and a contents page before you hand it in.
Making manuals easy to use
Help readers jump straight to the part they need in a long product guide.
Joining documents into one pack
After merging files, add a bookmark for each original document so readers can find them.
Limitations to know
Heading detection needs real text, so scanned pages must go through OCR first. Headings styled like body text can't be found automatically. The contents page is only added when all titles use Latin letters, and any existing bookmarks are replaced by the list you save.
PDF Bookmarks and TOC: common questions
Will it replace the bookmarks already in my PDF?
Yes. The saved file uses the list you edited. Start from the existing bookmarks if you want to keep and adjust what's already there.
Why weren't my headings found?
Headings need to be real text that's bigger or bolder than the body text. Scanned pages need OCR PDF first, and headings styled exactly like body text can't be told apart.
Do the page numbers printed on my pages change?
No. Only bookmark targets and contents page links are adjusted. Numbers printed on the pages stay as they are, so use Add Page Numbers afterwards if you want them to match.
Why wasn't a contents page added?
The contents page is only drawn when all titles use Latin letters, because it uses a standard PDF font. Your bookmarks are still saved.
How deep can bookmarks be nested?
Up to six levels. Each bookmark can be at most one level deeper than the one above it.