Crop PDF

About the Crop PDF

Crop the pages of a PDF without converting it. Drag the crop box on the preview, or type how much to cut from the top, right, bottom and left in millimetres, centimetres, inches or points, and apply it to all pages, odd pages, even pages or a list such as 1-3, 8-. Auto-crop finds the content of every page — text, pictures, drawings — and cuts the empty margins around it, page by page, keeping a little space you choose.

The crop is saved as the page’s crop box, the area PDF readers and printers show (ISO 32000-1 §14.11.2). The page content itself is not touched, so text stays sharp and searchable and pictures keep their full resolution. Your file is opened and saved in your browser and is never uploaded.

Common uses

• Making small print readable on a phone or e-reader by removing wide margins.
• Cutting scanner borders, punch holes and black edges off scanned pages.
• Preparing a page area — a chart, a table, a figure — for printing or for a presentation.
• Trimming the white space around slides, posters and drawings exported to PDF.

What cropping does to the file

A PDF page has a media box (the paper) and can have a smaller crop box: the part that readers display and printers print. This tool writes a new crop box for each page you crop. Nothing on the page is redrawn or recompressed, so the quality is exactly the same and the file size barely changes.

The parts outside the crop box are hidden, not deleted. They are still in the file: anyone can reset the crop box in a PDF editor and see them again, and text outside the box may still be found by search or copying. To remove confidential content for good, use Redact PDF.

How auto-crop finds the margins

Each selected page is drawn at about one pixel per point (72 dpi). Every pixel that is not almost white — darker than 250 on a 0–255 scale — counts as content, and the crop is the smallest rectangle that holds all of it, plus the space you chose to keep. Pages with no content at all are left as they are.

For scans, tick Scanned pages: then only pixels darker than 200 count, which ignores light grey paper, and rows or columns with fewer dark pixels than 0.4 % of the page’s shorter side (and never fewer than 3) are skipped, which ignores specks of dust. Dark scanner edges and shadows still count as content — cut those with typed margins instead.

Rotated pages and pages of different sizes

• Margins are measured on the page as you see it. On a page that is stored sideways and rotated for display, “top” is still the top edge on screen.
• Typed margins are cut from every selected page, so pages of different sizes keep the same margins rather than the same size. The summary shows the result for the page in the preview.
• If a page already had a crop, the new one is measured inside it.

Print boxes and the media box

Print-ready files can also have trim, bleed and art boxes. When they extend past the new crop they are clipped to it, so they stay inside the visible page. Under More options you can also shrink the media box, for the few converters and print services that ignore the crop box; the content outside is still kept in the file either way.

Limitations

• Cropping hides content outside the box but doesn’t remove it from the file — use Redact PDF for that.
• The crop can only make pages smaller; it can’t add margins or enlarge a page.
• Auto-crop treats coloured page backgrounds as content, so such pages are not cropped.
• Each run uses one set of margins (mirrored on even pages if you choose). To crop different pages differently, crop one set of pages, download the result and crop it again.
• Password-protected or restricted PDFs must be unlocked first with Unlock PDF.
• Saving changes the file, so existing digital signatures will show as invalid; the tool warns you when a file is signed.

Privacy

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