Crop PDF

What is Crop PDF?

Crop PDF is a free, browser-based tool that trims the margins off every page of a PDF. You give it four numbers — top, bottom, left, and right — and it cuts that much off each page, keeping the rest. It is handy for removing wide scanner borders, stripping printer crop marks, tightening slide decks for reading on a phone, or cleaning up the whitespace around a scanned document before merging or printing. Switch the unit between millimeters and percent to crop by an exact size or relative to each page, and a live preview shows the original next to the cropped first page so you can check the result before downloading.

How to use Crop PDF

1. Drag and drop a PDF onto the dropzone (or click to choose a file). The tool reads it and shows the page count and first-page size in points.
2. Pick a unit — open Settings to switch between millimeters (mm) and percent (%) of the page.
3. Enter how much to trim in the Top, Bottom, Left, and Right fields. Each value cuts that amount off the matching edge of every page.
4. Watch the cropped first page rebuild automatically next to the original; click either preview to enlarge it in a lightbox.
5. Click Download to save the cropped PDF, or use Reset to clear the file and start again.

Examples

Frequently asked questions

Is my PDF uploaded to a server?

No. Cropping runs 100% client-side in your browser with pdf-lib. The file is read and rewritten locally and is never uploaded, so even confidential documents stay private.

Does it crop every page or just the first?

Every page. The margins you enter are applied to all pages. The preview shows the first page so you can judge the result quickly.

What is the difference between mm and percent?

Millimeters trim a fixed physical size from each edge, so the same number works the same on any page. Percent trims relative to each page's own width or height, which is useful when pages differ in size.

Does cropping delete the trimmed content or just hide it?

It sets a smaller crop box and media box, so viewers and the next tool see only the cropped area. The trimmed region is no longer part of the visible page.

Why do I see an error that the margins are too large?

If the left plus right margins (or top plus bottom) leave nothing of the page, there is no area left to keep. Lower the values so some of the page remains, then it will rebuild.