Good reasons to crop PDF pages
- Reading on a small screen: research papers and scanned books often have wide margins. Cropped pages zoom larger on a phone or an ebook reader.
- Scanner borders: flatbed scans pick up the lid, shadows and a dark frame around the paper.
- One figure for a slide: crop a page down to a single chart, then turn it into an image with PDF to JPG.
- Print layouts: cut away crop marks and the extra area around a design that was exported for a print shop.
The tool works on one PDF at a time, up to 50 MB, so crop each file in its own pass.
Cropping hides content, it does not erase it
FileKiwi sets the crop box and media box of each page, the standard way to crop a PDF. Everything outside the box is hidden in every PDF viewer and is not printed. The hidden part is still inside the file, though, and a PDF editor can bring it back.
That matters if you crop to hide private details, such as an account number near the edge of a page. Crop first, then use Flatten PDF in Whole pages mode. Each page becomes an image of what is visible, so the hidden area is gone for good.
For the same reason, cropping does not make the file smaller. To reduce the size, use Compress PDF.
Crop or resize?
Cropping removes part of the page area. The page gets smaller and the content keeps its size. If your pages need to become exactly A4 or US Letter, use Resize PDF instead, which scales the content onto a standard paper size.
Whichever you use, leave a few millimeters of white space around the text. Pages cropped right up to the letters look cramped on paper, and many printers cannot print to the very edge.