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Crop PDF
Trim margins from every page. Free, no sign-up.
or drop it here
Crop PDF runs inside your browser — your file never reaches our servers.
How to crop PDF
Cropping sets a smaller visible box on each page. The underlying content is preserved, so a crop is reversible.
- Open your PDF. Any PDF, any number of pages.
- Set the margins to trim. Values are in points — 72 points is one inch.
- Crop and download. Every page gets the same visible box.
A crop box is an instruction, not a cut
Cropping writes a crop box onto every page: four numbers in points, measured from the bottom-left corner of the sheet, telling a reader which part of it to display. The page's media box and its content stream are left exactly as they were. Nothing is deleted and nothing is re-encoded — which is why cropping is not a way to make a file smaller, and why running the tool again on the cropped file with all four margins set to zero gives you the whole page back.
The corollary is the thing to know before cropping anything sensitive. The trimmed strip is still in the file: run the cropped PDF through PDF to Markdown and the running header you cropped away is still there in the output, because text extraction reads the content stream and takes no notice of the crop box. Cropping puts content out of frame; it does not remove it. If it has to be gone, that is Redact PDF, which rebuilds the page without the text underneath.
Choosing the numbers, and what stops you
The unit is the PDF point: 72 to the inch, so the default 36 trims half an inch and the maximum of 400 trims five and a half. A4 is 595 × 842 points and US Letter 612 × 792, so taking 72 off each side of a Letter-sized journal paper leaves 468 × 648 — about a third of the area gone. The same margins go on every page, each measured against that page's own size, so you cannot crop page 4 differently from page 5 here.
If the margins would leave less than 18 points of page, the tool stops and names the page rather than handing back a readable-looking sliver: "the horizontal margins add up to 800pt but page 3 is only 595pt wide". One thing nothing here does is turn a crop into a real trim. Flatten PDF in its Everything mode renders each page through the crop box but rebuilds that page at its original full size, so a cropped page comes back stretched to fill the sheet. Crop last, after anything that rebuilds pages as images.
Questions
Is cropping destructive?
No. It changes the crop box, not the page content, so the trimmed area still exists in the file and the crop can be undone later.
Why crop at all?
Academic PDFs often have huge margins that waste screen space. Cropping them makes a paper genuinely readable on a tablet or e-reader.
How do I undo a crop?
Run the tool again on the cropped file with all four margins set to 0. That resets the visible box to the full page, and the content is all still there because cropping never removed it. Keeping your original is still the safer habit.
Why did cropping not make the file smaller?
Because nothing was thrown away. A crop changes four numbers per page and leaves every image and glyph untouched. If the file also has to be smaller, compress it first and crop the compressed copy — Compress PDF may rebuild pages as images, and it rebuilds them at the original page size, which stretches a crop that is already there.
Can I crop one page differently from the rest?
Not in this tool — every page gets the same margins. The workaround is to extract the odd pages into their own file, crop that file, and merge the parts back together in order.
Are my files uploaded to a server?
No. Every tool on this site runs inside your browser, using the same engine as the Folia desktop app. Your file is read from your disk into your browser’s memory, processed there, and handed back as a download. It never crosses the internet, so there is nothing for us to store, leak or hand over.
Is there a file size limit?
We impose none. The only ceiling is your own device’s memory, which differs from one computer to another — so we read what your browser reports about this machine and show the resulting limit on the page. Light tools like merge and rotate handle far more than heavy ones like OCR, which must render every page. For anything larger, Folia for Desktop has no limit at all.
Is it really free? Do I need an account?
Yes, and no. Every tool is free and unlimited, with no watermark and no sign-up. Ads pay for the site, and your own computer does the work, which costs us nothing. Signing in with a paid Folia plan simply removes the ads.