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To crop a PDF, open it in a free PDF crop tool, drag a box around the part you want to keep, choose which pages to apply it to, and download the new copy. To remove white margins only, use automatic mode and let the tool find the edges of the content on each page.
This guide walks through both methods, shows how to do the same job in Acrobat and Mac Preview, and explains the one thing cropping does not do: it does not delete what you cut away.
How do you crop a PDF online for free?
You can crop a PDF for free in your browser, with no account and no upload. WoowPDF's tool works on the file on your own device, so the document never reaches a server.
- Open Crop PDF and choose your file.
- Pick manual mode to draw your own box, or automatic mode to trim white margins.
- In manual mode, drag the box or its edges and corners over the preview. The area outside the box is dimmed.
- Choose all pages or type a custom page range.
- Run the crop and download the file, which is named with "-cropped" at the end.
The result shows how many pages changed, for example 8 of 10, so you can spot pages that were skipped.
Manual crop or automatic trim: which should you use?
Use automatic trim when you only want to lose white space, and manual crop when you want to keep a specific area. The two modes behave differently across a document.
| Manual crop | Automatic trim | |
|---|---|---|
| Best for | Cutting out a table, chart or header | Removing wide white margins |
| Crop area | The same box on every selected page | Worked out separately for each page |
| Padding | You set the edge yourself | A padding setting keeps space around content |
| Blank pages | Cropped like any other | Left unchanged |
| Weak spot | Pages with different layouts | Scans with gray edges or shadows |
Manual mode stores the box as a share of the page rather than a fixed size, so it still lands in the same relative place if your pages differ in size. Check a few pages in the preview before you run it on a long file.
Why automatic trim can miss margins on a scan
Automatic trim looks for anything noticeably darker than white and treats it as content. That works well on a PDF made from a Word file or a web page, where the margins are pure white.
A scan is different. Page shadows, gray paper and specks near the edge all count as content, so the tool may leave more margin than you expected. When that happens:
- Switch to manual mode and draw the box yourself.
- Rescan with better lighting if you still have the paper. Our scan to PDF tool can help with a fresh copy.
- Crop only the pages that need it with a custom range.
Does cropping a PDF remove the hidden content?
No. Cropping changes the visible page area, but the text and images outside it normally stay inside the file. This is the point most crop guides skip, and it matters for anything private.
Someone with a PDF editor can often restore the original page, and text in the cropped area may still be found by search or copied out. So never use cropping to hide a name, account number or signature. To remove information properly, follow our guide on how to redact a PDF, which covers removing the content itself.
The same fact explains a common surprise: cropping usually will not shrink the file, because the data is still there. If you need a smaller file for email or an upload form, compress the PDF instead.
How to crop a PDF in Adobe Acrobat
If you have a paid Acrobat subscription, the crop tool sits in the edit tools. Menu names change between versions, so treat these as a guide.
- Open the file and choose Edit PDF.
- Select Crop Pages.
- Draw a rectangle around the area to keep.
- Double-click inside the rectangle to open the page box settings.
- Choose the page range and confirm.
Acrobat's online crop tool follows a similar path, with a border you resize on the first page.
How to crop a PDF on a Mac with Preview
Preview comes with every Mac and handles a simple crop, one page or selection at a time.
- Open the PDF in Preview.
- Choose Tools, then Rectangular Selection.
- Drag over the area to keep.
- Choose Tools, then Crop, and confirm.
- Save a copy, so the original stays untouched.
Preview also keeps the cropped content in the file, so the same privacy warning applies.
Crop, resize or rotate: which do you actually need?
Cropping is often confused with two other page jobs. Pick by the result you want.
| You want to | Use | What happens |
|---|---|---|
| Cut off margins or keep part of a page | Crop | The visible area gets smaller |
| Fit the document onto Letter or A4 | Resize PDF | The page gets a new paper size |
| Fix a sideways page | Change the orientation | The page turns, nothing is cut |
| Make the file smaller | Compress | Images and data are reduced |
A cropped page stays at its new smaller size. It will not fill a sheet of Letter on its own, so if you plan to print, set your print dialog to fit the page or resize the PDF afterward.
Common mistakes when cropping a PDF
Most crop problems come from a handful of small slips:
- Using the same box on mixed pages. A landscape chart in a portrait report can lose its edges. Crop those pages in a separate run with a page range.
- Cutting too close. Leave a little space around text so it does not touch the paper edge or a printer's unprintable area.
- Cropping to hide data. Hidden content can come back. Redact it.
- Overwriting your only copy. Keep the original until you have checked every page of the cropped file.
- Expecting a smaller file. Cropping changes the view, not the data. Compress as a separate step.
Ready to try it? Crop your PDF now. It is free and your file stays on your device.
Frequently asked questions
How do I crop a PDF for free?
Open a browser based tool such as WoowPDF's Crop PDF, choose your file, then drag a box or use automatic trim. Pick the pages and download the result. No account or software is needed.
Can I crop only one page of a PDF?
Yes. Choose a custom page range and enter that page number. The other pages stay exactly as they were, and the result tells you how many pages changed.
Does cropping a PDF make the file smaller?
Usually not. Cropping changes what is shown, while the content outside the crop stays in the file. To reduce the size, compress the PDF as a separate step.
Can a cropped PDF be restored?
Often, yes. The cut area normally remains in the file, so a PDF editor may be able to bring it back. Use redaction, not cropping, for anything confidential.
Why did automatic trim leave white space on my scan?
Shadows, gray paper and specks near the edge look like content to the tool, so it stops there. Draw the box in manual mode to get a tighter crop.
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- trim margins
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