PDF bookmarks
Silktide tests that long PDF documents include bookmarks - the clickable outline shown in a PDF viewer's sidebar. Bookmarks let readers jump straight to a section instead of scrolling through the whole document.
Why this matters
A long PDF without bookmarks can only be read linearly. Someone looking for one section of a 100-page report must scroll or search their way there, and someone using a or keyboard has to step through everything in between. Bookmarks give every reader a table of contents that works in any PDF viewer, cutting a multi-minute hunt to one click.
How to fix it
- Generate bookmarks from your headings in the source document:
- Microsoft Word: use the built-in heading styles, then export to PDF with "Create bookmarks using: Headings" enabled.
- Adobe InDesign: export with "Create Bookmarks from Structure" or from your table-of-contents settings.
- Or add bookmarks in a PDF editor such as Adobe Acrobat Pro, using the Bookmarks panel to link entries to each section.
- Give bookmarks clear names that mirror the document's structure - "Section 1" tells a reader nothing.
Cover the whole document, not just the first few sections.
How Silktide tests this
- Count the pages of each PDF document.
- Skip documents shorter than 21 pages - the criterion only applies to long documents, and since does not define "long", Silktide uses 21 pages or more, in line with Adobe's accessibility guidance.
- Flag long documents that contain no bookmarks.
Silktide tests whether bookmarks exist, not whether they are well named or cover every section - review those yourself when fixing a flagged document.