Practical use cases
- Trimming the wide black margins a flatbed scanner leaves around a scanned page.
- Cutting off a repeated header or letterhead across a document before extracting just the body text region.
- Removing a sidebar or margin notes column from a wide document to get a cleaner reading or printing area.
Why this is a real crop, not a mask
You draw the selection once, on the first page's preview. PDFDistrict stores that as a proportion of page 1's own width and height, then applies that same proportion to every page, scaled to each page's own dimensions — this is what makes it work even if later pages are a different physical size. It's a genuine crop: the page's actual CropBox is rewritten, which is the same property every PDF viewer and printer uses to decide what's visible, so nothing is just hidden behind a white box. The honest limitation: because the selection is defined relative to page 1, if other pages in the document have a meaningfully different layout or aspect ratio than page 1, the same proportional region may not land on the same visual content on those pages — this works best for documents where every page shares a similar layout.
Common problems
- You can't click Apply yet: it stays disabled until your drag is large enough to register — "Selection too small — drag a larger area" means try again with a clearly visible box.
- Later pages look cropped incorrectly: that's the limitation above — if the document mixes very different page layouts, crop it in smaller, more consistent batches instead of all at once.
- You want to start the selection over: use the reset button next to the preview to clear the current rectangle and draw a new one.