Crop PDF

Cut the margins off a PDF — top, right, bottom and left, across the whole document or only the pages you choose.

Runs on your devicePDFWorkingNo account needed

What this tool does

Every page in a PDF is defined on two rectangles. The media box is the sheet the page lives on; the crop box is the window a reader actually draws. Crop PDF subtracts your four trim amounts from the current media box and writes the smaller rectangle into the crop box, and into the media box as well unless you switch that off. Nothing is redrawn, so the page keeps its text layer and its images at their original resolution.

Measuring always starts at the media box, and a crop box the file already carries is overwritten rather than read. A press-ready PDF with bleed, or one already cropped elsewhere, therefore comes back showing the trimmed sheet rather than the tighter window it opened with — which can expose more of the page instead of less. Check what a viewer shows before and after when the document did not come straight out of a scanner or an office suite.

The four numbers are read the way you see the page, not the way the file stores it. A page carrying a 90 degree rotation is displayed on its side, so what you call the top is the left edge in the file's own coordinates; the trims are mapped through each page's rotation before they are applied. A 10 mm top trim therefore takes 10 mm off the top of the page in front of you, even in a scan where a few sheets came through sideways. Amounts are entered in millimetres, points or inches, with the arrows moving half a unit at a time, and the page field accepts all, odd, even, a single number, a range such as 2-5 or a list like 1,4-6,last.

This runs in the browser tab with pdf-lib and the document is not uploaded. The limit to understand before relying on it is that cropping hides content rather than removing it. Whatever falls outside the new rectangle is still stored in the file, so a text extraction, a copy-paste, or anyone who resets the boxes will find it again, and the file does not shrink — Compress PDF is what reduces size, and Redact PDF is what destroys text rather than framing it out. The same four figures are applied to every page you select, so a document whose margins vary from page to page takes one pass per group.

How to use it

  1. Add the PDF. Drop in one document or several. Each is cropped with the same settings in turn and comes back with -cropped added to its filename.
  2. Choose the units and the four amounts. Millimetres, points or inches. Each edge starts at 10 and can be set independently, and at least one of them has to be above zero or the job is refused.
  3. Name the pages to crop. Leave the field on all, or type odd, even, a single page, a range such as 3-8, an open range such as 7-, or a mixed list.
  4. Decide what happens to the media box. Also shrink the media box is on by default, which keeps printers and converters in step with what a reader shows. Turn it off to change the display window alone.

Processing & privacy

Runs on your device. Your file is processed directly in this browser.

Common use cases

A scan with a dark border

Flatbed and sheet-fed scanners leave a grey or black strip where the lid did not meet the paper. A few millimetres off each edge removes it without scanning the document again.

Slides exported with a fixed footer

A deck saved to PDF often carries a branded band along the bottom of every slide. One bottom trim across all pages takes it off the whole file.

Reclaiming room before an n-up or booklet run

Generous PDF margins waste paper twice over once pages are placed two or four to a sheet. Trimming them first gives the content more of the printed area.

Tightening a figure for placement

A chart or map exported on a full A4 page sits inside a wide empty border. Cropping to the drawing itself lets it be dropped into a report at a sensible size.

Questions

Does the document leave my device?
No. pdf-lib reads the file and rewrites the page boxes inside this tab, so the document stays on your machine. That library is served from this site and fetched on the first crop of a session; once it is in the page, further crops run with the network disconnected.
Does cropping make the PDF smaller?
Barely. Only the rectangles change — the content beyond them is still stored — so the byte count moves a little either way as the file is rewritten, and no more than that. Compress PDF is the tool that reduces size.
Can the cropped-off content be recovered?
Yes. The boxes are metadata, so resetting them brings the hidden area straight back into view, and text extraction ignores them altogether. If the aim is to get rid of sensitive material rather than tidy the edges, Redact PDF removes the text itself.
What does the media box checkbox change?
The crop box is the window most readers display; the media box is the sheet the page is defined on. Viewers generally honour the crop box on its own, but printers and some converters read the media box, which is why both are shrunk by default.
Can I drag a box over a preview instead of typing figures?
No. The crop is described by four margin amounts and applied to every selected page. There is no visual selection and no detection of where the white space actually ends, so cropping to a particular area means measuring it and entering the numbers.
Why was my crop refused?
The trim itself is stopped by three things: all four amounts left at zero, a negative amount, or margins that would leave a page with nothing on it. That last message names the page and gives its real size in points, so you can work out what will fit. Separately, a page number outside the document and a file that cannot be read as a PDF are turned away before any trimming begins.
What happens if I crop the same file twice?
It depends on the media box setting. With it on, the second pass measures from the already-reduced sheet and the trims accumulate. With it off, the media box is untouched, so the second pass measures from the original sheet and replaces the earlier crop instead of adding to it.
What if the PDF is locked with a password?
It is refused, with a message pointing at Unlock PDF. Remove the password there first, using a password you already hold, then crop the result.

Related tools

  • Merge PDF — Combine several PDFs into one document in the order you choose.
  • Split PDF — Split one PDF into separate documents by page range.
  • Compress PDF — Reduce PDF file size while preserving the quality that matters.
  • PDF to JPG — Export every page of a PDF as a JPG image.
  • JPG to PDF — Turn one or many JPG photos into a single PDF.
  • Protect PDF — Add a password and set permissions on a PDF.