Cropping a PDF is not the same as cropping a photo. When you crop a photo, you permanently remove pixels. When you crop a PDF, you are adjusting the "crop box" — a boundary that tells PDF viewers what part of the page to display. The content outside the crop boundary still exists in the file; it is just hidden. Some tools do remove the content permanently, which gives a smaller file size.
The most common reasons to crop a PDF: removing large white margins from a scanned document, cutting out a specific section of a page to use elsewhere, or resizing a page that was saved with the wrong dimensions.
How to crop a PDF for free
Method 1 — Convert to image, crop, convert back
This is the most accessible free method and works on any device:
- Convert the PDF page to a PNG using Filero's PDF to PNG tool.
- Crop the PNG image using your device's built-in photo editor (Photos on Windows, Preview on Mac, Photos on iPhone).
- Convert the cropped PNG back to PDF using Filero's Image to PDF tool.
This approach permanently crops the content and works well for single pages. For multi-page documents, it is more manual effort.
Method 2 — Adobe Acrobat (paid)
Acrobat has a dedicated Crop Pages tool under Tools > Edit PDF > Crop Pages. You draw a crop box directly on the page, set precise measurements, and apply it to one page or all pages at once. The most capable option for complex cropping tasks, but requires a paid subscription.
Method 3 — Preview on Mac (free, built-in)
Open the PDF in Preview. Select the Markup toolbar (the pencil icon). Draw a selection box over the area you want to keep. Go to Tools > Crop. Preview adjusts the page to show only the selected area. Save the file. Note: Preview's crop adjusts the crop box rather than permanently removing content — the cropped area can be restored in Acrobat if needed.
Removing margins from scanned documents
Scanned documents often come with large grey or white borders from the scanner bed. These add visual clutter and make the actual content feel small on screen. Cropping removes these borders and makes the document cleaner.
For a quick fix on a scanned document: convert to PNG, use Preview (Mac) or Photos (Windows) to crop the borders, then convert back to PDF. This takes about 60 seconds per page.
Extracting a specific section from a PDF page
If you need just a chart, a table, a logo, or a specific paragraph from a PDF page, the image method works well:
- Convert the page to PNG.
- Open the PNG in any photo editor.
- Crop to the section you need.
- Save as PNG or convert back to PDF.
This is much faster than trying to extract the element directly from the PDF, and the result is a clean image you can use anywhere.
Frequently asked questions
Does cropping a PDF reduce the file size?
It depends on the method. Adjusting the crop box in Acrobat or Preview does not reduce the file size because the hidden content is still in the file. Converting to an image and back does reduce the size because the cropped pixels are genuinely removed.
Can I crop all pages at once?
In Adobe Acrobat, yes — you can apply the same crop to all pages simultaneously. With the image conversion method, you would need to process each page separately, which makes it impractical for long documents. For bulk operations on multi-page PDFs, Acrobat is worth considering.
Will cropping affect the text — can I still copy it?
If you use the image conversion method, the result is a PDF containing an image — the text is no longer selectable or searchable. If you use Acrobat or Preview's native crop, the text remains intact and searchable because only the visible area changes, not the underlying content.
Ready to try it?
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