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Crop PDF
Free PDF cropper: drag a crop box, auto-detect whitespace, or type exact margins. Crops every page and several files at once in your browser. No upload, no watermark.
How to use Crop PDF
- Drop one or more PDFs.
- Drag the crop box or click Auto-detect margins.
- Download the cropped PDFs.
How to crop a PDF online for free
PaperKit crops a PDF three ways: drag a crop box over a live preview of the page, click Auto-detect to trim the white margins automatically, or type exact margins in points. The crop is applied to every page, and you can drop several PDFs to crop them all in one run. Nothing is uploaded, so scanned contracts, bank statements, and exam papers stay on your device.
Drag the crop box on the page preview
After you drop a PDF, PaperKit renders the page and draws a crop box over it. Drag any edge or corner to change the crop, or drag the whole box to move it. The four margin fields update as you drag, and the After panel shows the real cropped output before you download. Page through the document with the arrows to check the crop on other pages.
Auto crop: detect the content and trim the whitespace
Click Auto-detect margins and PaperKit scans the rendered page for ink, then sets the crop to the content bounds with a 6-point safety margin. Auto-detect across all pages scans up to 40 pages and keeps the smallest margin on each side, so a wide table on page 12 is never cut off. It works on scans, slides, and e-books, and you can still nudge the box afterwards.
Crop all PDF pages at once, and several PDFs at once
The same margins are applied to every page in the document, which is what most people need when a scan has a dark border, a PDF has printer marks, or an e-book has wide margins that waste space on a tablet. Drop more than one file and each PDF is cropped with the same settings and downloaded separately, so a folder of scanned statements is done in one click.
Units: points, inches, and centimeters
Margins are measured in PDF points, the native unit of the PDF format. 72 points equal 1 inch and roughly 28.35 points equal 1 centimeter. To trim half an inch from each side, enter 36. To trim 1 cm, enter 28. The default of 20 points (about 7 mm) removes typical scanner borders without touching body text.
Crop a PDF to a specific size
Subtract the size you want from the size you have, then split the difference between opposite edges. An A4 page is 595 × 842 points and US Letter is 612 × 792 points. To turn A4 into a 555 × 802 point page, trim 20 points from each of the four edges. If you need to change the page size without trimming content, use the Resize PDF tool instead.
Remove white margins for reading on a tablet or e-reader
Academic papers and scanned books often have 1-inch margins that shrink the text on a small screen. Trimming 40 to 60 points from each side makes the text noticeably larger on a Kindle, iPad, or phone without changing the content, and the file stays a normal PDF that any reader can open.
What cropping does and does not do
Cropping sets the visible page box (both the MediaBox and CropBox) so viewers and printers show only the area you kept. The original page content stays inside the file, so cropping is reversible with a PDF editor and should not be used to hide confidential text. To permanently remove pages, use Delete PDF Pages; to strip author and title fields, use Remove PDF Metadata.
Private, free, and no server-side limits
Because the crop runs with pdf-lib in your browser, there is no upload queue, no watermark on the output, no signup wall, and no server-side file size limit. Very large PDFs are limited only by your device memory. A single file downloads as paperkit-cropped.pdf; several files keep their own names with -cropped added. A cropped file can be cropped again, and the second crop is measured from the visible page edges.
Next steps
- Resize PDF pages instead of trimming them
- Delete whole pages from a PDF
- Extract only the pages you want to crop
- Compress the cropped PDF
Related PDF tools
- Resize PDF — Resize PDF pages to A4, US Letter, or custom dimensions in millimeters or points.
- Rotate PDF — Rotate selected pages of a PDF by 90, 180, or 270 degrees and save the result.
- Compress PDF — Reduce PDF size by re-encoding images and stripping metadata. Works for most scanned PDFs.
Frequently asked questions
How do I crop a PDF for free without uploading it?
Open PaperKit Crop PDF, drop the file, enter how many points to trim from each edge, and click Crop PDF. The crop runs locally in your browser and the result downloads immediately, with no upload, account, or watermark.
Can I crop every page of a PDF at once?
Yes. The margins you enter are applied to all pages in a single pass, so a scanned book with a dark border on every page is fixed in one step.
How do I crop a PDF to a specific size?
Work in points (72 points = 1 inch). Subtract the target width and height from the current page size and split the difference between opposite edges. For example, trimming 20 points on all four sides of an A4 page (595 × 842) gives 555 × 802.
Does cropping a PDF reduce quality or remove the content permanently?
Cropping does not re-render or compress anything, so text stays sharp and searchable. It changes the visible page box only; the trimmed area still exists inside the file and can be restored with a PDF editor, so do not use cropping to redact sensitive information.
Can I select the crop area visually?
Yes. Drop the PDF and drag the crop box over the page preview. Edges, corners, and the whole box are draggable, and the numeric margins update as you go.
Can PaperKit crop the white margins automatically?
Yes. Auto-detect margins finds the content on the current page; Auto-detect across all pages scans up to 40 pages and uses the smallest margin per side so nothing is cut off.
Can I crop several PDFs at once?
Yes. Drop multiple files and every PDF is cropped with the same margins in one run. Each cropped file downloads separately with "-cropped" added to its name.
Can I crop only some pages?
The crop applies to every page of a file. To crop only certain pages, extract them first with Extract PDF Pages, crop that file, then merge it back with Merge PDF.