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Crop PDF

Free PDF cropper and trimmer: drag a crop box, auto-detect white margins, or type exact sizes. Crops every page in your browser. No upload, no watermark.

How to use Crop PDF

Drop one or more PDFs.
Drag the crop box, click Auto-detect margins, or type exact margins.
Download the cropped PDFs.

How to crop a PDF online for free

Crop PDF online without uploading: PaperKit is a free PDF cropper that trims margins three ways. Drag a crop box over a live page preview, click Auto-detect to trim white space, or type exact margins in points. The same crop applies to every page, and you can drop several PDFs to crop them in one run. Everything runs with pdf-lib in your browser, so scanned contracts, bank statements, and exam papers never leave your device.

How to crop a PDF in three steps

1. Drop one or more PDFs onto Crop PDF. 2. Drag the crop box, click Auto-detect margins, or type left, right, top, and bottom values in points. 3. Check the After preview, then download. A single file saves as paperkit-cropped.pdf; several files keep their names with -cropped added. No account, no watermark, and no upload queue.

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 PDF: detect content and trim 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.

Trim PDF margins on every page, and on several PDFs

Most people open a trim tool to remove dark scanner borders, printer marks, or unused white space. The same margins apply to every page in the document, which is what you usually want for a scanned book or a batch of statements. Drop more than one file and each PDF is cropped with the same settings and downloaded separately, so a folder of scans 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. Cropping trims content; it does not scale the drawing. If you need to change the sheet size without trimming, use Resize PDF instead.

Crop vs resize: when to trim and when to change page size

Use Crop PDF when you want to remove margins, borders, or a footer and keep the remaining content at its original scale. Use Resize PDF when a printer or submission portal needs a different page size (A4, Letter, A0) and you are changing the sheet, not cutting content away. Many "crop PDF to A4" searches actually need Resize PDF with the A4 preset.

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 cropped file can be cropped again, and the second crop is measured from the visible page edges.

Next steps

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 — Shrink a PDF by re-encoding the photos and scans inside it at the quality you choose, or fit it under 100 KB, 500 KB or 1 MB, all in your browser.

Frequently asked questions

How do I crop a PDF for free without uploading it?

Open PaperKit Crop PDF, drop the file, drag the crop box or 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.

How do I trim PDF margins online?

Drop the PDF, click Auto-detect margins to trim whitespace, or type the same left, right, top, and bottom values for every page. Auto-detect across all pages keeps the smallest margin per side so nothing is cut off.

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. To change sheet size without trimming, use Resize PDF.

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 auto crop a PDF and trim white margins?

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.