How to Crop PDF Margins and Scanner Borders
Trim wide white margins or dark scanner edges from every page of a PDF — set millimetres per side, watch the preview, download. Text stays sharp.
3 min read ·
To crop the margins of a PDF, open Crop PDF, add the file, choose how much to cut from each edge — 5, 10, 15 or 20 mm all round, or each side separately — and watch the shaded preview. Click Crop every page and download. Nothing is re-compressed, so text stays sharp and selectable.
Crop a PDF step by step
- Open Crop PDF and add your PDF. Page 1 appears as a preview.
- Click a preset under Same on every side — 5, 10, 15 or 20 mm — or type separate amounts for Top, Bottom, Left and Right.
- Check the preview: the darkened edges will be cut off, and the blue frame shows what stays.
- Click Crop every page, then Download cropped PDF.
Every page is cropped by the same amounts, which suits documents with consistent margins — books, papers, reports, scans from the same scanner.
Why crop a PDF?
- Reading on a phone or tablet: academic papers and books often have wide margins; cropping them makes the text noticeably bigger on a small screen.
- Scanner borders: flatbed scanners leave dark or grey edges around the page. Cropping a few millimetres removes them.
- Slides exported to PDF with large white borders.
- Printing: removing excess white space before printing several pages per sheet with N-up PDF makes each page larger.
How much to crop
A4 paper is 210 × 297 mm; US Letter is about 216 × 279 mm. Typical margins:
| Document | Usual margin | Safe crop |
|---|---|---|
| Word documents | 25 mm | 15–20 mm |
| Academic papers | 20–30 mm | 10–20 mm |
| Scanner border | 2–5 mm | 5 mm |
| Slides with white frame | varies | check the preview |
Leave a little white space around the text — cropping right to the edge makes pages harder to read and printers may cut off the edge.
Pages that differ
The same crop is applied to every page. If some pages have different margins — a landscape table in a portrait report — the preview shows page 1 only, so check the downloaded file. Landscape and rotated pages are cropped as you see them: the "top" is always the top of the page as it's displayed.
If a few pages need different treatment, split them out with Split PDF, crop each part separately, and merge them back with the PDF Merger.
Straighten scans first
A page scanned at a slight angle or sideways has uneven margins, and cropping it evenly cuts into the text on one side. Turn sideways pages upright with Rotate PDF first, then crop, and use a smaller crop for crooked scans so no text is lost.
Cropping hides — it doesn't delete
Cropping sets the visible area of each page. The content outside it is hidden, not removed: it's still inside the file, and some PDF editors can reveal it again. Never crop to hide confidential information — a name in a margin note, an account number in a footer. Use Redact PDF, which removes the content for real.
Crop or resize?
- Crop removes edges and makes the page smaller.
- Resize keeps all the content and fits the page onto a different paper size — A4 to Letter, for example. Use Resize PDF for that.
Frequently asked questions
Does cropping reduce quality?
No. Nothing is re-rendered; only the visible area changes.
Can I undo a crop?
Keep your original file. Cropping again with 0 mm on every side doesn't restore the old edges.
Is the PDF uploaded?
No — cropping happens in your browser.