How to merge or split a PDF

Choose Merge or Split at the top of the tool.
To merge: drop in two or more PDFs. Each row shows its page count. Reorder with the arrows, remove anything you added by mistake, then press Merge PDFs to download merged.pdf.
To split: drop in one PDF. Pick a method — extract page ranges, split every N pages, or one file per page.
For range extraction, type something like 1-3, 5, 8-. A live preview tells you exactly which pages will be included before you commit.
Optionally set Rotate all pages, then press Split PDF. Multi-part splits download one file after another.

How it works

A PDF is a collection of objects — page trees, fonts, images, content streams — tied together by a cross-reference table. Merging is not a matter of gluing two files end to end: the objects from each document have to be renumbered and copied into a new document, with fonts and images carried across so nothing breaks.

This tool uses pdf-lib, a pure-JavaScript PDF library that runs in the browser. Merging loads every source document, copies each one’s page objects into a fresh document in list order, and serialises the result. Splitting does the same in reverse: a new document is created for each output and only the requested page objects are copied into it.

Because pages are copied rather than re-rendered, nothing is lost. Text stays as text you can search and select, vector graphics stay resolution-independent, and embedded images keep their original compression. The output is usually close to the sum of the inputs, sometimes slightly smaller where shared resources are de-duplicated.

Rotation works through the page’s /Rotate entry, a multiple of 90 degrees stored in the page object. The tool adds your chosen angle to whatever each page already had, so a page that was already sideways ends up correct rather than doubly rotated.

Method	Output	Typical use
Merge	One `merged.pdf`	Combining scanned receipts or signed pages
Extract ranges	One PDF with the pages you listed	Pulling a chapter or an appendix out
Split every N pages	One file per group of N	Breaking a long scan into batches
Each page as a file	One file per page	Splitting a batch scan into individual documents

Worked examples

Combining a signed contract. You have contract-p1.pdf (3 pages), signature-page.pdf (1 page) and annex.pdf (5 pages). Add all three, drag the signature page into second position, and merge. The result is a 9-page merged.pdf in exactly that order.

Pulling one chapter out of a report. A 48-page report where chapter 3 runs from page 17 to page 24. Switch to Split, choose “Extract page ranges”, type 17-24, and you get an 8-page report_pages_17-24.pdf.

Bursting a batch scan. Twelve invoices scanned into one 12-page PDF. Choose “Each page as a file” and you get scan_part_01.pdf through scan_part_12.pdf, zero-padded so they sort correctly in a file manager.

Fixing a sideways scan while splitting. A scanner produced a document rotated 90 degrees counter-clockwise. Set Rotate all pages to 90 degrees clockwise and the extracted pages come out upright.

Tips and common mistakes

Page numbers are physical, not printed. Page 1 is the first sheet in the file, even if the printed number on it says “iv” or “12”.
A trailing dash is your friend. 20- means “page 20 to the end” and saves counting. -5 means “the first five pages”.
Backwards ranges are rejected on purpose. 8-3 is almost always a typo, so the tool asks you to write 3-8 rather than quietly guessing.
Duplicates are dropped. 1-4, 3 gives you pages 1 to 4 once. A PDF cannot contain the same page object twice in this workflow.
Allow multiple downloads. A 12-part split is 12 separate downloads, and browsers block that by default until you say yes.
Large documents live in memory. A 50 MB scan is held entirely in this tab, so give it a moment and avoid running it on a low-memory phone.
Truly encrypted files need decrypting first. If a PDF asks for a password before it displays, no browser tool can open it without that password.

Privacy

Your documents are never uploaded. The browser reads the file locally with the File API, pdf-lib parses and rewrites it in this tab, and the result is handed to you as a blob download. There is no server component, no processing queue and no temporary copy on anyone else’s disk. Closing the tab discards everything, which makes this safe for contracts, medical records, payslips and anything else you would not want to hand to a third-party website.

Frequently asked questions

How do I merge PDFs in a specific order?

Add every file, then use the up and down arrows next to each row until the list matches the order you want. Files are combined top to bottom, and the numbered badge on each row shows its position.

What page range syntax does the split tool accept?

Comma-separated pages and ranges, such as 1-3, 5, 8-. A trailing dash means "to the last page" and a leading dash means "from page 1". Spaces are ignored and duplicate pages are removed automatically.

Can this tool open password-protected PDFs?

Only partly. PDFs with an owner password that merely restricts printing or copying usually open fine. A PDF that needs a user password to be read at all cannot be decrypted here — open it in a reader, enter the password, and save an unprotected copy first.

Does splitting or merging reduce the quality of a PDF?

No. Pages are copied as complete objects, so text stays selectable, vectors stay sharp and embedded images keep their original data. Nothing is rasterised or re-compressed.

Why does my browser ask about downloading multiple files?

Splitting into several parts triggers one download per file. Browsers ask for permission the first time a page does that. Allow it, or you will only receive the first part.

Are my documents uploaded anywhere?

No. The PDF is read into memory in this tab and rewritten by a JavaScript PDF library running on your own device. There is no server, no upload and no stored copy.

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Last reviewed: September 21, 2026

Merge and Split PDF