How to Crop a PDF — Trim Margins Off Every Page (2026)
Table of Contents
You export a slide deck to PDF and it comes out ringed with dead space. You scan a book chapter and every page has a three-centimetre white border. You save a screenshot to PDF and it prints tiny, marooned in the middle of the sheet. In all three cases the fix is the same: crop the PDF so the page edges hug the content. This guide shows the fastest free way to do it in a browser, explains what cropping does under the hood (it is not what most people assume), and compares four tools so you can pick the right one.
1. Quick Answer
How to crop a PDF: open Convertlo's free crop tool at convertlo.pro/crop-pdf.html, drop your file, and set how much to trim from the top, right, bottom, and left as a percentage of each page. Click Crop and the same crop box is applied to every page, then saved into the downloaded PDF. It runs entirely in your browser, so nothing is uploaded and no account is needed. One thing to know: cropping sets the page's crop box, which hides and un-prints the margins — the original content outside the box is retained in the file, not permanently deleted. To truly discard it, print the cropped PDF to a new PDF.
2. Why Crop a PDF at All
Cropping is not cosmetic fiddling — it solves concrete problems that make PDFs harder to read, print, and reuse.
Remove wide scan margins
Flatbed and phone scans leave thick white borders around the actual page. Trimming them makes the text larger on screen and stops printers from shrinking the content to fit.
Tighten slide exports
Slides exported to PDF often carry letterbox bars or presenter margins. Cropping to the live area gives you a clean, edge-to-edge handout.
Trim screenshots for printing
A screenshot saved to a full A4 or Letter page prints as a small island. Crop the empty sheet away so the image fills the paper.
Standardise a mixed document
Merged PDFs can arrive with uneven borders. A single percentage trim across all pages evens them out for a consistent read.
The common thread: the useful pixels are already there, they are just surrounded by space that gets in the way. Cropping brings the page boundary in to meet the content.
3. How PDF Cropping Actually Works
This is the part almost every "crop PDF" tutorial gets wrong, so it is worth being precise. Every page in a PDF has several bounding boxes. The one cropping changes is the crop box (CropBox) — the rectangle that defines the visible and printable region of the page.
When you crop, the tool does not erase anything. It shrinks the crop box so that only the region you kept is displayed and printed. The text, images, and vector art that used to sit in the margins are still fully present in the file — they are simply outside the visible window, so viewers and printers ignore them.
Why this matters: a cropped PDF can be "un-cropped" by resetting the crop box, because the original content is retained. That is convenient if you make a mistake, but it means cropping is not a way to permanently strip sensitive content out of the margins. For that you need to flatten the file — covered in section 6.
Convertlo's tool applies the trim as a percentage of each page's own dimensions. If you set 8% on the left, it removes 8% of that page's width from the left edge. Because it is relative, the same setting works correctly whether a page is A4, Letter, or an odd scanned size — and it applies to all pages at once. If a trim would leave a page smaller than a tiny minimum, that page is left alone so you never end up with a zero-size page.
4. Crop a PDF in Your Browser (Convertlo)
The browser method needs no install and no upload — the PDF is read, cropped, and re-saved locally using JavaScript. That makes it the right choice for contracts, medical scans, or anything you would rather not send to a server.
Go to convertlo.pro/crop-pdf.html in Chrome, Edge, Firefox, or Safari. It works on desktop and mobile, with no signup.
Drag the file onto the drop zone or click to browse. The file stays on your device — nothing is transmitted anywhere.
Enter how much to cut from the top, right, bottom, and left as a percentage. For typical scan margins, start at 5–10% per side and nudge from there. The same values apply to every page.
The tool sets the new crop box on all pages and rebuilds the PDF. Download the cropped file — it opens in any PDF reader with the margins gone.
Crop your PDF now — free, private, no upload
Trim margins off every page in one click. Nothing leaves your device.
5. Every Method Compared
Four tools cover essentially every crop-a-PDF situation. Here is how they stack up on the things that actually matter — whether they hit all pages at once, whether you have to install anything, and whether your file stays private.
| Method | All pages at once? | Installs? | Private? |
|---|---|---|---|
| Convertlo (browser) | Yes — one click | No install | Yes — local only |
| Adobe Acrobat (Crop tool) | Yes — page range | Paid desktop app | Yes — local |
| macOS Preview (rectangle select + crop) | Only if you select all pages first | Built into macOS | Yes — local |
| Briss (desktop app) | Yes — visual auto-grouping | Java app download | Yes — local |
Adobe Acrobat
Acrobat's Crop tool (Tools → Edit PDF → Crop, or double-click a drawn rectangle) is precise and lets you type exact margins and apply them to a page range. It is the gold standard if you already pay for Acrobat Pro, but it is a heavyweight paid install for a one-off crop.
macOS Preview
Preview is free on every Mac. Use the rectangle-select tool to draw the region you want to keep, then Tools → Crop (⌘K). The catch: it crops the current page unless you select every page in the sidebar first, so for long documents it is fiddlier than a percentage-based tool.
Briss
Briss is a free Java desktop app that shines on scanned books. It stacks all pages and lets you draw crop rectangles visually, automatically grouping odd and even pages so left and right pages crop correctly. Powerful, but it requires a Java download and has a dated interface.
6. Cropping vs. True Content Removal
Because cropping only hides the margins, there are two situations where you need an extra step.
You need the hidden content gone for good. If the margins contain something confidential — reviewer notes, a header with a name, redaction that must not be recoverable — a crop alone is not enough, since resetting the crop box brings it back. Flatten the cropped file instead: open it in any PDF viewer, choose File → Print, and select Save as PDF (or "Microsoft Print to PDF" on Windows). Printing re-writes only the visible area into a brand-new document, so the previously hidden content is not carried over.
Flattening by print-to-PDF can rasterise text or drop selectable text layers depending on the viewer. Keep your cropped-but-not-flattened copy until you have confirmed the flattened version still looks and behaves the way you need.
You need a smaller file. Cropping does not shrink file size, because the hidden objects stay in the document. To actually reduce size: crop first, flatten to discard the hidden area, then run the result through a compressor such as Convertlo's PDF compressor. That order gives you a tight, small, margin-free PDF.
7. Frequently Asked Questions
How do I crop a PDF for free without installing software?
Does cropping a PDF actually delete the margin content?
Can I crop every page of a PDF at once?
How do I remove wide white margins from a scanned PDF?
Will cropping a PDF reduce its file size?
Cropping a PDF is a two-minute job once you know that it is the crop box you are moving, not the content you are deleting. For the fast, private version, trim every page in your browser and download — no install, no upload.
Trim the margins off your PDF
Free, browser-based, all pages at once. Your file never leaves your device.