Crop margins and resize PDF pages
Trim white margins from every page, or resize a whole document to A4 or Letter with the content scaled to fit. Both operations run in your browser, and cropping never touches the actual page content — only what's visible.
Crop & Resize
CropBox trim or scale-to-fit · non-destructive
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How to Crop & Resize
- Add your PDF. Drag the file onto the drop zone. The current page count is shown so you can confirm you have the right file.
- Choose crop or resize. Crop trims a margin from all four sides of every page. Resize scales the whole page to a new paper size.
- Set the amount. For cropping, drag the margin slider. For resizing, pick A4 or Letter — content is scaled to fit, never stretched unevenly.
- Download. Save the result. The original file on your device is untouched.
Cropping doesn't delete anything
PDF pages have a MediaBox — the full page — and a CropBox, which is what a viewer actually displays. Cropping here changes only the CropBox, trimming the visible area without touching the underlying content stream.
That has a genuinely useful property: the crop is reversible by any PDF tool that lets you reset or adjust the CropBox, and nothing about the original text or images is lost. If you scanned a page with wide printer margins and just want to trim the white space for a cleaner look, this is the right tool — it never rasterizes or re-renders anything.
Resizing scales content, it doesn't crop
Resize is a different operation: it changes the actual page dimensions to a standard size like A4, and scales everything on the page proportionally to fit inside it. Nothing is cut off — a page that was slightly too wide for A4 shrinks slightly; a page much smaller than A4 grows to fill it.
This matters when you're combining pages from different sources — say, a scanned Letter-size page and an A4 report — into a single consistently-sized document before printing or merging.
Frequently asked questions
Does cropping delete the trimmed content permanently?
No. Cropping changes the page's CropBox, which controls what a viewer displays. The full page content remains in the file — the crop can be undone or adjusted by any PDF tool that lets you edit the CropBox.
Will resizing distort my content?
No. Content is scaled proportionally to fit the new page size, so aspect ratio is preserved. A page slightly too wide shrinks slightly; nothing is stretched unevenly.
Is my file uploaded?
No. Both cropping and resizing happen entirely in your browser using pdf-lib, and the file never leaves your device.
Can I crop different amounts on different sides?
Not currently — the same margin is trimmed from all four sides. If you need an asymmetric crop, the Organize Pages tool's rotate-and-arrange view is a reasonable workaround for individual pages.
Does this work on scanned PDFs?
Yes. Cropping and resizing both operate on the page geometry, not the content type, so they work identically whether the page is text or a scanned image.
Will the cropped PDF still open normally in other readers?
Yes. CropBox is a standard part of the PDF specification, honoured by every mainstream PDF viewer, browser and printer.