PDF Splitter

PDF Splitter extracts subsets of pages from a PDF into one or more output files. The processing uses pdf-lib to copy page objects byte-for-byte from the source into new documents — there is no re-rendering, re-compression, or quality loss. Embedded fonts, vector graphics, hyperlinks, and image resolution all match the original exactly. pdfjs-dist handles thumbnail rendering so you can preview pages before extracting.

Three modes are available. Range mode accepts any combination of single pages and ranges (e.g., "1-3, 5, 8-10, 15"). With the Each range as a separate file option enabled, "1-3, 5-8" produces two PDFs; with it disabled, you get a single combined PDF containing those pages in order. Per-page mode produces one PDF per page, useful for splitting a batch of invoices that were combined into one file. Interval mode splits at regular boundaries (every 5 pages, every 10 pages) — handy for chapter-style splits when natural section breaks don't exist.

Multiple output files are bundled into a single ZIP archive using JSZip on the fly, so a 100-page split into 100 individual PDFs downloads as one zip rather than 100 browser save dialogs. Filenames are auto-generated with zero-padded indices (page-001.pdf, page-002.pdf) so they sort correctly in any file manager.

Form fields, annotations, and bookmarks belong to specific pages and are preserved when those pages are extracted. The document's outline (TOC) is rebuilt to reference only the surviving pages — entries pointing to dropped pages are removed.

Encrypted PDFs cannot be parsed by pdf-lib until they are unlocked, so password-protected files must be cleared first with the PDF Password tool. Existing digital signatures are invalidated by splitting because the document changes — this is part of the PDF signing standard.

Browser memory is the practical limit. PDFs up to about 200 MB and 1000 pages split comfortably on a modern laptop. Generating thumbnails for every page is the slow step for very long documents; the actual splitting itself is fast because pdf-lib copies bytes rather than re-rendering. For 1 GB+ documents, a desktop tool like qpdf or Adobe Acrobat is faster.

After splitting, common follow-ups are PDF Compressor (to shrink the new files for email), PDF Merger (to recombine subsets in a different order), or PDF OCR (to make extracted scanned chapters searchable).