The Complete Guide to Splitting PDFs in Your Browser
Four split modes, live preview, byte-for-byte fidelity, and the privacy model.
1. What splitting a PDF means
Splitting a PDF means taking one input document and producing two or more output documents, each containing a subset of the original pages. Common reasons: emailing a chapter instead of a 300-page book, posting only the signature page of a contract, or trimming a bank statement down to a single month for an application.
2. Choosing a split mode
- By ranges — give a comma-separated list of ranges. Each range becomes its own output file.
1-3, 5-7produces two files: one with pages 1–3, one with pages 5–7. Open-ended ranges like10-mean “page 10 to the end”. - Every N pages — every Nth page starts a new file. N=2 splits the document into pairs (pages 1–2, 3–4, 5–6…). N=1 is equivalent to “each page”.
- Each page — every page becomes a standalone single-page PDF. Handy for extracting one page from a large report without thinking about ranges.
- Target size — the tool greedily packs pages into output files until the next page would push the result over your MB cap, then starts a new file. Useful when you need each chunk to fit an email attachment limit.
3. Privacy and quality
The split runs entirely client-side with pdf-lib — no upload, no server, no telemetry. Pages are copied byte-for-byte viacopyPages, so text, fonts, images, and annotations come through identical to the source. There is no re-encoding and no quality loss in either direction.
Conclusion
Splitting is the precise counterpart to merging: take one document, produce many. Use ranges for surgical extraction, Every N pages for even chunking, Each page for single-PDF archives, and Target size for email-friendly cap-bounded output. The live preview tells you exactly what you will get before you download, and the whole operation runs in your browser with zero quality loss.