How to Crop a PDF Online (Trim Margins or Straighten a Scan)
Crop a PDF to remove white margins or straighten a tilted scan. A clear guide to rectangle cropping, free four-corner cropping, and when to use each, free and in your browser.
What cropping a PDF does
Cropping changes the visible area of each page without deleting any pages. Use it to cut off wide white margins, remove a scanner’s black border, or zoom in on the part of the page that matters. The text and layout inside the kept area stay exactly where they were.
Rectangle crop: trim clean margins
In Rectangle mode a crop box sits on the first page. Drag the box to move it and pull any corner or edge to resize, then download. This keeps the PDF as real text you can still select and search, so it is the right choice for normal, born-digital PDFs where you just want tidier margins.
Free corners: straighten a tilted scan
Photographed or scanned pages are often slightly skewed, so a straight rectangle cannot line up with the document. Switch to Free corners and drag each of the four corners on its own to match the edges of the page. The tool then straightens (deskews) that region into a clean rectangle. Because the page is redrawn, these pages are saved as a sharp image.
The crop applies to every page
The area you set on the first page is applied to all pages in the document. That is ideal for a scanned book or report where every page has the same margins. If your pages differ a lot, crop them in smaller batches so each set shares a layout.
Which mode should I use?
Choose Rectangle when the PDF was created digitally and you only need neater margins, because it preserves selectable text and file size. Choose Free corners when you are working from a photo or a skewed scan and need the content straightened. When in doubt, try Rectangle first.
Private and free
Cropping runs entirely in your browser, so your PDF is never uploaded to a server. There is no account, no watermark, and no limit on how many files you crop. When you are done you can merge, compress, or sign the result with the other Becoderr PDF tools.
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