PDF Source

The most common way to make a FlipBook is to upload a single PDF and let the plugin turn each page into a FlipBook page. This article walks through every option on the PDF source flow, including PDF password handling and how to optimize a PDF for best results.

When to use this source

Pick Single PDF when:

  • You have one PDF that should become one FlipBook (e.g. catalog, magazine, ebook, annual report).
  • The PDF is under 50 MB for the smoothest experience (larger PDFs work but load slower).
  • The PDF is text-based (not a scan of pages). Scanned PDFs work for viewing but features like search and Read Aloud need OCR'd text.

If you need to combine multiple PDFs into one book, see Multi-PDF Source. If your content is a stack of images, see Image Gallery Source.

Step-by-step

1. Open a new FlipBook

Go to FlipBooks → Add New. Type a title at the top.

2. Pick Single PDF

On the Content tab, three source-type cards appear:

  • Single PDF (selected by default)
  • Multiple PDFs
  • Image Gallery

Leave Single PDF selected — it's the default.

3. Upload your PDF

The card shows a dropzone with a Select PDF button. You have two ways to add the PDF:

Option A — Drag and drop the PDF file from your computer onto the dropzone. WordPress uploads it automatically.

Option B — Click "Select PDF" to open the WordPress media library:

  • The Media Library tab shows PDFs you've already uploaded.
  • The Upload Files tab lets you pick a new PDF from your computer.

Once a PDF is attached, you'll see:

  • The PDF's filename and size.
  • A small thumbnail of the first page.
  • A Remove button to detach and pick a different PDF.
  • A Replace button to swap the PDF without losing other FlipBook settings.

4. Configure PDF options

Below the upload area you'll find these settings:

Setting

What it does

PDF Password

If your source PDF is password-protected, paste the password here. Saved in the protection tab too — see below.

Disable Annotations

Skip rendering PDF embedded links, form fields, and annotations. Useful for very heavy PDFs where the overlays slow things down.

(More PDF-related settings — like watermarks, copy prevention, etc. — live on the Protection tab. See Protection and DRM.)

5. Publish

Click Publish in the top-right corner. The FlipBook is now live at yoursite.com/flipbook/your-slug/.

How the PDF becomes a FlipBook

The plugin renders PDF pages on the fly using PDF.js (a Mozilla-built JavaScript PDF engine that runs in the visitor's browser). Each page becomes a high-quality image rendered into a 3D plane.

  • Page 1 loads first so visitors can start reading immediately.
  • Remaining pages render in the background as the visitor flips, in priority order (next/previous spreads first).
  • Render quality is controlled by the Render Scale setting under Display → Rendering. Higher scale = sharper at zoom, but slower to render. The default of 2 is a good balance for most documents.

PDF password handling

If your PDF is password-protected:

  1. On the Content tab, paste the password into the PDF Password field (or on the Protection tab — both points are linked).
  2. Save the FlipBook.

The password is stored encrypted and used only to render the PDF. Readers never see the password — they just see the rendered pages. They won't have access to the original encrypted PDF either, since downloads can be blocked via the Protection tab.

Optimizing your PDF for the best experience

A well-prepared PDF produces a much better FlipBook. Three things matter:

File size

  • Aim for under 50 MB. Larger PDFs work but loading is noticeably slower.
  • Free tools to compress: Smallpdf, ILovePDF, Adobe Acrobat's built-in optimizer.
  • High-res print PDFs are typically 300 DPI — for web display, 150 DPI is usually plenty.

Text vs. image

  • Text-based PDFs (exported from Word, Pages, InDesign, Google Docs) are ideal. Text is selectable, searchable, and accessible.
  • Image-only PDFs (scans of physical pages) work for viewing but cannot be searched, read aloud, or accessibly interpreted by screen readers. Run OCR on scanned PDFs first (Adobe Acrobat's "Recognize Text" or free tools like Tesseract).

Standard page size

  • Stick to standard sizes like A4 (210x297mm) or US Letter (8.5x11 inches).
  • Unusual aspect ratios (extreme wide formats, square pages) render but may look odd in the FlipBook frame. Test with a draft first.

Common operations

Replacing the PDF

To swap the PDF without rebuilding the FlipBook:

  1. Click Replace under the PDF preview.
  2. Pick the new PDF from the media library.
  3. Save.

Existing settings (display, toolbar, hotspots tied to a page number) are preserved. Hotspots positioned on pages that no longer exist in the new PDF won't render.

Removing the PDF

Click Remove. The source becomes empty, and you can pick a new PDF or switch source types.

Switching to a different source type

If you decide to switch from Single PDF to Multiple PDFs or Image Gallery later, click the other source card. Your PDF stays in the media library; the FlipBook just uses the new source going forward.

Notice when you have content in multiple source types

If you've previously added content to multiple source types (e.g. a Single PDF and an Image Gallery), the editor shows a notice: "You also have content in [other source type]." This is just a reminder — only the currently-selected source type is used at publish time.

Featured Image (cover)

The PDF's first page is auto-used as the cover thumbnail in the Image Link block/shortcode by default.

If you want a custom cover image (separate from page 1):

  1. Set the Featured Image in the publish sidebar (right side of the editor).
  2. The Image Link block/shortcode with cover="true" uses the Featured Image instead of page 1.

This is useful when you want a polished branded cover that's different from the first page of the actual document.

Troubleshooting

"Failed to load PDF" or blank pages on the front end.

  • Confirm the PDF actually uploaded — open the FlipBook editor and verify the PDF preview shows.
  • Check WordPress upload limits. PHP's upload_max_filesize and post_max_size settings need to be higher than your PDF's size. Talk to your host if you need to raise these.
  • Try the PDF in a private browser window (rule out cache).

"This document is password-protected" error. The PDF needs a password and you haven't provided one. Add it under PDF Password on the Content tab.

Pages look pixelated when zoomed. Increase Render Scale in FlipBooks → Settings → Display → Render Scale. Try 3 or 4. Note: higher scale uses more memory on the reader's device.

Pages take a long time to load.

  • Your PDF may be large or high-res. Compress it.
  • Disable PDF Link Overlay if your PDF has many annotations — these add overhead.
  • Lower Render Scale to 1.5.

Embedded links or form fields don't work.

  • Confirm PDF Link Overlay is enabled (Content tab or General tab).
  • Confirm Disable Annotations is off.
  • Note that form fields require enabling Form Viewer in the toolbar.

The PDF has all blank pages even though it's correct. The PDF might be encrypted with a permissions password that blocks rendering. Open it in Adobe Acrobat → File → Properties → Security to check. Remove the password protection or paste it in the PDF Password field.

Right-to-left content doesn't display correctly. Pick a right-to-left language under General → Language (Arabic, Hebrew, Persian, etc.). The viewer flips its toolbar and page-flip direction automatically.

Next steps

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