Some PDF pages carry their content in the middle and a sea of white around it: the scanner's lid border framing every page of a scan, the desk visible around a photographed document, a slide or diagram exported onto a full-size page with the graphic floating small and centered. The content is fine — it's the page that's the wrong size for it. Cropping fixes exactly that, by trimming the empty margins off the page. Crop PDF does it in your browser, with nothing uploaded and nothing re-rendered.
Where all the white comes from
- Scanner beds. The glass is bigger than the page, so every scan carries a border — and a lid that isn't perfectly seated adds a dark strip to it.
- Photographed pages. Camera shots include the desk, the table edge, or whatever was behind the paper.
- Slide and poster exports. Design tools center content on a standard page, leaving wide bands of empty space on every side.
- Content pasted onto bigger pages. Material built for one page size, placed unchanged onto another.
None of this affects the content — but it shrinks everything on screen, wastes paper in print, and makes every page look like a draft. The white border is also louder than people expect: a half-inch frame around a scan reads as "unprocessed" to exactly the audiences — clients, courts, reviewers — you most want to look organized for.
How cropping works
You choose a percentage, and that fraction of each page is trimmed from all four edges. Only the page boundaries change — the content itself is never re-rendered.
It's a uniform trim, not a rectangle you draw. That makes it fast and predictable — one number decides the whole job — and it makes it the wrong tool for a page whose content sits off-center in its own peculiar way. For scan borders and symmetric dead margins, which is most of the cases above, it's exactly right: the border came from one machine or one export setting, so one trim removes it everywhere.
How to crop a PDF
- Open Crop PDF and drop in your file — up to 100 MB, processed locally on your device.
- Choose the percentage to trim from each edge.
- Crop and download the result.
Nothing is re-rendered
Cropping here is a page-boundary operation, not an image-editing one. Nothing is re-rendered or recompressed — the page boxes are simply set smaller, so full quality is preserved. Text stays sharp, images keep their pixels, and the file's content is untouched inside its new boundaries. This is the difference between cutting the page down to size and taking a screenshot of it: the first moves edges, the second rebuilds everything.
One margin, every page
The margin is applied to every page, scaled to that page's own size, so mixed page sizes are handled correctly — a document that mixes A4 and Letter pages gets a proportionally consistent trim on each. What there isn't is per-page cropping: one percentage, applied everywhere. If a single page genuinely needs a different crop from the rest, this uniform approach isn't the right fit. But for the jobs cropping is usually wanted for — scan borders, export margins — the borders are consistent precisely because they came from one source.
Choosing a percentage that doesn't bite
Because the same trim hits every page, the tightest page in the document sets the limit for all of them. Two habits keep the choice safe:
- Start small. A few percent removes most scanner borders and export margins. Large percentages are for pages that are genuinely mostly white.
- Mind the edges. Headers, footers, and existing page numbers live at the edges — the same place the crop cuts. Trim past them and they're gone, on every page at once.
Work in small steps and look at the result between them: crop, open the output, see where the margins landed, and go again from the original if the cut went too far or not far enough. Because the tool never touches your source file, an iteration costs nothing but a moment — the safest way to find the exact percentage is to approach it rather than to guess it.
The right crop is the smallest one that removes the dead space: exactly the white, and nothing that was doing work.
Crop first, number later
If cropping is one step in a longer cleanup, its position in the sequence matters. Crop before adding page numbers, not after — stamped numbers sit near the page edge by convention, exactly where a later crop would cut them off. The same logic orders cropping before anything else that places content near the margins: trim the pages to their final size first, then decorate them.
Cropping also pairs naturally with the rest of a scan cleanup. A misfed stack usually needs its pages reordered and the sideways ones rotated before the borders are worth addressing — and once the pages are straight, sequenced, and cropped, Add Page Numbers can finish the job with a clean numbering pass. Each step feeds the next; only the last one stamps anything permanent.
Keep the original — and know about encrypted files
Two last things worth knowing. First, keep the original file: cropping produces a new download rather than editing your file in place, and the untouched original is your undo. Second, if your PDF is password-protected, the cropped copy is rebuilt without that protection — keep the original if you need it secured, and share the cropped copy deliberately.