Medium: 150 DPI, 85% quality. Default. Good balance of clarity and size.
High: 300 DPI, 95% quality. Sharpest previews, larger files. Use for document-heavy sites.
Changes apply to newly uploaded PDFs. Use the Tools tab to regenerate existing previews.
Default Load Behavior
Controls when the full PDF.js viewer loads. Can be overridden per embed.
Click (default): Preview image shown. Full viewer loads when user clicks "View Document".
Visible: Full viewer loads automatically when the embed scrolls into the viewport (IntersectionObserver).
Immediate: Full viewer loads on page load. Use sparingly, since it adds JavaScript to initial load.
Default Width
CSS width value for the viewer container. Default: 100%. Can be overridden per embed with the width attribute.
Toolbar Controls
Toggle which buttons appear in the viewer toolbar. Each setting can be overridden per embed:
Download: Show/hide the download button (default: on)
Print: Show/hide the print button (default: on)
Fullscreen: Show/hide the fullscreen button (default: on)
Preload Viewer
When enabled, the PDF.js library is preloaded in the background after page load (using ). Reduces the delay when the user clicks to view a PDF. Default: off.
Cache Duration
How long generated preview images are cached. Default: 30 days. The cache stores preview metadata to avoid re-processing PDFs that haven't changed.
Gutenberg Block Settings
When inserting the PDF Viewer block, each instance has its own settings panel:
