Crop PDF — Trim Page Margins

Crop PDF — Trim and Adjust PDF Page Margins

Cropping a PDF means adjusting the visible area of its pages by removing unwanted margins, white space, or content from the edges. Our free online PDF Crop tool lets you specify exactly how many millimeters to trim from each side of every page — giving you precise control over the final page size and layout.

Why Crop a PDF?

There are many practical reasons why you might need to crop the pages of a PDF:

Removing excessive white space: Scanned documents, academic papers, and printed-to-PDF files often have large, unnecessary margins that waste space when viewed on screen or printed. Cropping removes this dead space and makes the content fill the page more naturally.

Preparing for printing: If you need to print a PDF on a specific paper size but the document has margins that push the content off-center or waste paper, cropping the margins beforehand gives you a better print result.

E-reader and tablet optimization: PDF files viewed on e-readers (like Kindle or Kobo) or tablets often look tiny due to large white margins. Cropping the margins makes the text and images much larger and easier to read without zooming.

Removing watermarks or headers/footers: Some PDFs contain page headers, footers, or watermarks in the margin areas. By cropping those margins, you can effectively remove those elements from the visible area.

Presentation slides: Academic papers converted from LaTeX or Word often have generous margins not suitable for slide presentations. Cropping to a tighter margin gives a cleaner look.

Cutting out specific content: If a PDF page contains diagrams or charts surrounded by excessive white space, cropping brings those visuals to the foreground.

How Our PDF Crop Tool Works

Our tool uses the FPDI library to process your PDF with millimeter-precision cropping:

1. You specify the number of millimeters to remove from each side: Top, Right, Bottom, and Left.
2. The tool reads every page of the PDF and calculates the new page dimensions.
3. Each page is resized to the new dimensions (original size minus the specified crop values).
4. The content is repositioned so the visible area corresponds to the cropped region.
5. The resulting PDF has the same number of pages but with adjusted, smaller page sizes.

Understanding Crop Values

Crop values are specified in millimeters (mm) for each of the four sides independently:

• Top: Removes the specified number of mm from the top of each page.
• Right: Removes the specified number of mm from the right side.
• Bottom: Removes the specified number of mm from the bottom.
• Left: Removes the specified number of mm from the left side.

For example, a standard A4 page is 210×297mm. If you crop 20mm from each side, the resulting page is 170×257mm (170 = 210−20−20, 257 = 297−20−20).

You can crop asymmetrically — for example, removing only the bottom margin of a page that has a large footer, without affecting the other sides.

Typical Crop Values for Common Use Cases

| Use Case | Suggested Crop | |---|---| | Removing thin borders from scanned docs | 2–5mm per side | | Eliminating large white margins in papers | 15–25mm per side | | E-reader optimization | 10–20mm per side | | Removing page headers/footers | 15–20mm top/bottom | | Trimming printed-to-PDF pages | 10–15mm per side |

Important Notes

• Cropping in PDF does not remove content — it adjusts the visible viewport. The content outside the crop area is still present in the file data but is hidden from view. This is a standard PDF cropping behavior.
• Applying very large crop values may cut into actual text or images. Preview the result before sharing.
• All pages are cropped uniformly with the same values. Per-page cropping is not currently supported.
• The output PDF file size may vary slightly depending on the content density.

Features

• Millimeter precision: Specify exact crop values for each of the four sides.
• All pages processed: Every page in the PDF is cropped uniformly.
• Preserves content: Text, images, fonts, and formatting are all retained.
• Fast and free: No registration, no watermarks, instant download.
• Privacy: Your uploaded files are deleted immediately after processing.