How to crop a PDF page

Cropping happens under Pages > Crop pages in PDF by Zaweba: drag a rectangle round the part of the page you want to keep, and everything outside it is cropped away. If what you're after is simply getting rid of empty borders, Pages > Remove white margins trims them automatically.

People crop for all sorts of reasons. Big white margins make a document hard to read on a phone. A scan picks up the dark edge of the scanner lid. A page has a header or a filing note you don't want to print. Or you need just the chart from a page, sized to that chart.

Dragging a crop

Go to the page and choose Pages > Crop pages. Drag a rectangle over the area to keep. Leave a little space round text and pictures, because cropping too tight can clip the edge of a letter or a border.

Page commands in PDF by Zaweba act on the pages chosen in the thumbnails, or on the current page. After cropping, look through a few pages in case one has its content in a slightly different place from the rest.

Removing white margins

Remove white margins looks at each page and trims the empty border round its content. It's the faster choice for documents with generous margins that you want to read more comfortably on a small screen, and for slides or drawings exported with a lot of space round them.

It works best on pages with a clean white background. A scan with grey edges or specks of dust may not trim as far as you expect, and for those a dragged crop gives you more control.

Setting exact margins

For print jobs, rough dragging isn't always good enough. Pages > Set page boxes lets you set the crop, trim, bleed and art boxes as margins in millimetres. The crop box is the area a viewer shows and prints. The trim box is the finished size of a printed piece after cutting, the bleed box the area including artwork that runs off the edge, and the art box the meaningful content. Printers sometimes ask for these to be right.

View > Show page boxes draws all four on the page, so you can check them before sending the file to print.

What cropping does and doesn't do

Cropping changes what's shown and printed. It doesn't destroy the content outside the crop, which is still in the file. That's useful, because you can loosen a crop later, but it means cropping is not a way to hide private information. Anyone with the right tool could show it again. For that job, use the redaction tools, which remove the content for good.

If you want the page to be a different paper size, not just a smaller visible area, Pages > Change page size is the command to use. It scales the content to fit or centres it.

Each crop is an undo step, and nothing is written to the file until you save, so experiment freely. Save as keeps the original copy alongside.

PDF by Zaweba is free software for Windows that works offline with no account, so your documents are trimmed on your own PC.