Use the free View PDF Bookmarks below: your PDF never leaves your browser — all work happens on your device, and nothing is uploaded to any server.
The hidden map inside your PDF
Many PDFs carry a hidden chapter list called bookmarks, or an outline. Open a well-made ebook or manual in a PDF reader and the sidebar shows its chapters, clickable, nested into sections. That sidebar is the outline. But not every reader shows it clearly, and some PDFs bury it. This tool pulls that hidden map into the open: upload a PDF and see its full bookmark tree, with the target page of every entry.
Why does that matter? Because the outline tells you how a document is organised before you read a word. A manual with a clear outline is navigable; one without is a wall of pages. An editor checking a manuscript can see at a glance whether the chapters are in order and nothing is missing. A student can see the structure of a textbook chapter before diving in. A reader deciding whether a long report is worth their time can scan its map first.
How to use it
Upload your PDF and press the button. The tool reads the outline with pdf.js and displays it as a nested list: chapters at the top level, sections indented beneath them, subsections beneath those. Each entry shows its target page number, so you know exactly where each section starts. The whole job runs in your browser; your file is never uploaded.
If the PDF has no bookmarks, the tool says so plainly. That is itself useful information: it tells you the document has no internal navigation, and that a contents page or bookmarks would improve it.
Reading the tree
A healthy outline mirrors the document. Top-level entries are chapters or major parts. Indented entries are sections within them. If you see a chapter with no sections, it may genuinely be short — or its sections may never have been bookmarked. If you see deeply nested entries, the document is finely structured, which suits reference use but can overwhelm a casual reader.
Watch for oddities. A bookmark pointing to the wrong page suggests the outline was built from an older version of the document. Duplicate titles suggest a merge that was never cleaned up. A single bookmark for a hundred-page document suggests the author exported without chapter marks. Each of these is a small quality signal that is invisible until you look at the tree.
Bookmarks versus a contents page
Bookmarks and contents pages do related but different jobs. Bookmarks live in the reader sidebar: one click jumps you there, and they work on screen but not on paper. A contents page is a visible page inside the document: it works in print and on screen, but jumping requires finding the page number. Good documents have both. This viewer shows you the bookmark side; if it is empty, that is your cue to consider adding one.
For authors, the lesson is practical: structure your source document with real headings, and most PDF exporters will turn those headings into bookmarks automatically. A document built with styled headings gains navigation for free; one built with bold text that merely looks like headings gains nothing.
Uses beyond reading
Archivists use outline checks to verify that digitised books kept their structure. Publishers use them to confirm a manuscript exported completely. Teachers use them to plan lessons around chapter boundaries. And anyone merging PDFs can check that the merged file kept the bookmarks of its parts — merges often drop them silently, and this viewer catches that loss in seconds.
Privacy and limits
Your PDF is read locally and never sent anywhere. The tool shows titles and target pages only; it does not show or change your document content.
One limit: page numbers shown are the PDF page positions, counted from the first page of the file. If your document has front matter with roman numerals, the bookmark page and the printed page number may differ by the number of front pages. That is normal for PDF tools, and the offset is constant across the document, so it is easy to allow for.
Common questions
My PDF has chapters but shows no bookmarks. Why? The chapters were probably not marked as headings when the PDF was made, so no outline was created.
Can I edit the bookmarks here? No. This tool views them; editing needs a PDF editor.
Does it work on scanned PDFs? Only if the scan software added an outline, which is rare. Most scans have none.