Put several PDF pages on one sheet

How PDF N-up works

The file is read with a FileReader, rewritten in memory and offered as a download. This is why large PDFs are limited by your device's RAM rather than by an upload size limit. A 200 MB scan never crosses the network, so the slowest part is your own disk.

That is the whole architecture: static files, one script, no upload endpoint to leak or log. Close the tab and the work is gone.

Why the words stop being selectable

An N-up sheet has to place several differently sized pages into a fixed grid. The reliable way to do that in a browser is to render each page to an image and draw that image into its cell — which is why the output looks identical and behaves like a scan.

The alternative, embedding the original page objects and scaling them through a transformation matrix, keeps text selectable but breaks on rotated pages, mixed page sizes and transparency. For a handout you are about to print, the image route wins on predictability.

Choosing 2, 4, 6 or 9

Two per sheet on A4 gives each page roughly A5 — comfortable for reading. Four is the usual handout compromise: legible body text, cramped footnotes. Six and nine are for reference material you will not read line by line, such as slides or a lecture deck printed to annotate.

At 2× resolution per page, a 300-page document needs real memory. If the tab stalls, split the file first and do it in halves — the output order stays correct either way.

Good to know

• Works offline once loaded, including on flights and in locked-down networks.
• No file size limit beyond your device's own memory.
• Free to use, with no account and no usage counter.
• Results are produced locally, so they are not logged or shared with anyone.

Questions