# PDF Bookmarks

Add bookmarks (an outline) to a PDF and save it. Create them one per page, from estimated headings, or by pasting "page: title" lines. Afterwards you can still change levels, titles and pages. The page contents do not change.

- URL: https://tools.itlibra.com/en/pdf-bookmarks
- On-device・No upload
- Last updated: 2026-10-23

## How to use

1. Drop a PDF or click “Choose file”. Any existing bookmarks appear as a tree of levels.
2. To create them automatically, choose “One per page”, “Estimate headings” or “Paste to create”. Each one replaces the current bookmarks.
3. Edit names and page numbers, then add or remove items. Move items up or down with the arrow buttons (or Alt+↑ / Alt+↓). Change levels with the demote and promote buttons.
4. Choose “Show bookmarks when the file opens”, then click “Create PDF with bookmarks”.
5. The saved file is read back and its count is checked. Then download it.

## Use cases

- Add chapter bookmarks to a long report or thesis
- Add one bookmark per page to a scanned document
- Turn a table of contents written as text into bookmarks
- Fix the names or page numbers of existing bookmarks

## What it does

### Three ways to create

One per page; estimated headings, which lists candidates from text size; or paste "page: title" lines, where indentation makes levels.

### Edit as a tree

Change levels, names and pages in one list. Add, remove and change levels with buttons. Reorder with the buttons, or with Alt+↑ / Alt+↓.

### Japanese titles

Titles are written as UTF-16, so Japanese bookmarks display correctly and open in other PDF viewers.

### Checked after saving

The saved file is read back, and it is only offered when the bookmarks match what you made.

### Contents unchanged

Only the bookmark tree and the “show on open” setting change. Text, images and annotations are not re-rendered or recompressed.


## Supported formats

### Input

- PDF (.pdf)

### Output

- PDF (.pdf)


## Capability matrix

| Feature | Support | Notes |
| --- | --- | --- |
| Create one per page, from estimated headings, or from pasted lines | Supported | — |
| Read and edit existing bookmarks (names, pages, levels) | Supported | — |
| Show the bookmarks panel when the file opens | Supported | — |
| Estimate headings in a scanned PDF with no text layer | Not supported | No candidates appear when the PDF has no text. Run OCR first |
| Guarantee that estimated headings are correct | Partial | Candidates come from text size only. Some lines that are not headings may appear; untick them |
| Set the zoom or position a bookmark opens at | Not supported | Bookmarks only point to a page |
| Bookmark colour, bold and other styling | Not supported | Lost on save. Only names, pages, levels and open/closed state are kept |
| URL or script bookmarks (JavaScript and similar) | Not supported | Only bookmarks that go to a page are written |
| Add bookmarks to a password-protected PDF | Not supported | Remove the protection first |
| Digitally signed PDFs (keeping the signature) | Not supported | Bookmarks can be written, but the signature is invalidated on save |

## Limits & notes

- Up to 300 MB and 5,000 pages per file. A file can have up to 10,000 bookmarks, nested up to 33 levels deep.
- Heading estimate reads the first 500 pages. Paste accepts up to 1,000 lines, and each title up to 200 characters.
- Encrypted PDFs and password-protected PDFs cannot be opened.
- Works on a smartphone too, but for PDFs with many bookmarks a desktop browser is easier to edit in.

## Privacy & safety

Reading the PDF, making the bookmarks and saving all happen in your browser. Your PDF is never sent to a server.

## FAQ

### How do I add a table of contents (bookmarks) to a PDF?

Open the PDF and create bookmarks with “One per page”, “Estimate headings” or “Paste to create”. Then fix the names or pages and click “Create PDF with bookmarks”.

### Can I edit or delete PDF bookmarks?

Yes. Existing bookmarks appear as a tree. Change names and pages, and remove a row with its delete button. Items under a removed row move up one level.

### Can I create PDF bookmarks from headings automatically?

Yes. “Estimate headings” lists candidates based on text size, and you choose which to add. A scanned PDF with no text layer gives no candidates.

### Will Japanese bookmarks show as garbled text?

No. Titles are written as UTF-16. The file is read back and only saved when the count and content match.

### Does adding bookmarks change the PDF contents?

No. Only the bookmark tree and the “show when the file opens” setting change. Text and images are not re-rendered or recompressed.

### Is my PDF uploaded?

No. Everything is processed in your browser and never sent to a server.