How to Crop PDF Pages: Remove Margins & Resize

When and Why You Need to Crop a PDF

PDFs come with fixed page dimensions, and those dimensions are not always what you need. A scanned document might have enormous white margins from the scanner bed. A PDF exported from a design tool might include bleed areas and crop marks intended for a print shop. A presentation slide deck might have aspect ratio issues when embedded in a web page. A research paper might waste screen real estate with excessively wide margins that made sense on paper but are frustrating on a laptop screen.

Cropping a PDF adjusts the visible page area without altering the underlying content. Think of it like using a picture frame: you choose which part of the page to show, and the rest is hidden. In most PDF implementations, the cropped content is not actually deleted -- it is just concealed by redefining the page boundaries. This means cropping is often reversible, which is useful if you make a mistake or need to restore the original dimensions later.

Common reasons to crop a PDF include:

• Removing scanner artifacts and excessive white space from scanned documents
• Trimming print margins for on-screen reading
• Removing headers, footers, or page numbers from specific pages
• Adjusting page dimensions to match a specific output requirement
• Cropping a large-format PDF (like an architectural drawing) to focus on a specific area
• Preparing PDF content for embedding in presentations, websites, or other documents

This guide covers every method for cropping PDF pages: online tools, desktop software, and command-line automation. Whether you need to crop a single page or batch-process hundreds of pages with identical margins, the right approach is here.

Understanding PDF Page Boxes

Before cropping, it helps to understand how PDF defines page dimensions. A PDF page actually has multiple "boxes" that define different boundaries:

When you "crop" a PDF in most tools, you are changing the CropBox. The MediaBox remains unchanged, which is why the content outside the crop area is not deleted -- it is just hidden. Some tools give you the option to modify the MediaBox directly, which permanently removes the content outside the crop area.

Understanding this distinction matters when security or file size is a concern. If you crop a PDF to remove sensitive content from the visible area but only change the CropBox, the hidden content is still in the file and can be recovered by anyone who changes the CropBox back. For true removal, you need to modify the MediaBox or re-render the document.

Method 1: Crop PDF Online with ConvertIntoMP4

The fastest way to crop a PDF without installing anything is through an online tool. The PDF cropper on ConvertIntoMP4 handles the process directly in your browser.

Step-by-Step

Step 1: Open the cropper. Navigate to the PDF cropper in any modern browser.

Step 2: Upload your PDF. Drag your file onto the upload area or click to browse. The tool loads a preview of your PDF pages.

Step 3: Set the crop area. Use the visual crop handles to define the area you want to keep. Drag the edges inward to remove margins, or enter precise pixel or inch values for exact crop dimensions.

Step 4: Apply to all pages or individual pages. Choose whether to apply the same crop to every page or adjust each page individually. For documents with consistent margins (like scanned books), applying to all pages saves significant time.

Step 5: Download. Click the crop button and download your cropped PDF. The file is ready to use immediately.

For documents that need more than just cropping -- like page reordering, rotation, or removal -- the PDF page organizer provides a comprehensive set of page manipulation tools in one interface.

Method 2: Adobe Acrobat Pro

Adobe Acrobat Pro provides the most precise PDF cropping capabilities, including numeric control over all five page boxes and the ability to apply different crops to different pages.

Cropping with the Crop Tool

1. Open your PDF in Adobe Acrobat Pro
2. Go to Tools > Edit PDF
3. Click Crop Pages in the toolbar (or right-click a page and select Crop Pages)
4. A crop rectangle appears on the page -- drag its handles to define the crop area
5. Double-click inside the crop rectangle to open the Set Page Boxes dialog
6. Fine-tune the exact crop values in inches, centimeters, or points
7. Choose the page range to apply the crop (current page, all pages, or a specific range)
8. Click OK to apply

The Set Page Boxes Dialog

This dialog gives you precise control:

• CropBox: The area viewers will see (standard crop)
• TrimBox, BleedBox, ArtBox: For print production
• Page Range: Apply to all, even/odd, or a specific range
• Margins: Set exact values for top, bottom, left, and right
• Remove White Margins: Auto-detect and remove white space (useful for scanned documents)
• Revert to Original: Undo the crop by resetting to the original MediaBox

Removing White Margins Automatically

Acrobat can automatically detect the content boundaries on each page and crop to remove white space. In the Set Page Boxes dialog, check Remove White Margins and Acrobat calculates the crop based on actual content edges. This is particularly useful for scanned documents where margins vary from page to page.

Method 3: Using Preview on macOS

Preview, the built-in macOS PDF viewer, supports basic PDF cropping:

1. Open the PDF in Preview
2. Click the Markup toolbar button (or press Shift+Command+A)
3. Select the Rectangular Selection tool
4. Draw a rectangle around the area you want to keep
5. Go to Tools > Crop (or press Command+K)
6. Preview crops the page to your selection

Important notes about Preview cropping:

• Preview only crops one page at a time -- you cannot batch-crop all pages simultaneously
• The crop modifies the CropBox, so the hidden content technically remains in the file
• If you undo the crop (Command+Z) before saving, the original dimensions are restored
• After saving, the crop is preserved but can still be reversed by other tools that modify the CropBox

For multi-page PDFs where you need to apply the same crop to every page, Preview is impractical. Use an online tool or Acrobat for batch cropping.

Method 4: Command-Line Cropping with Ghostscript

For automation and batch processing, Ghostscript provides powerful command-line PDF cropping:

# Crop a PDF to specific dimensions (in points, 72 points per inch)
gs -o output.pdf -sDEVICE=pdfwrite \
  -dDEVICEWIDTHPOINTS=432 -dDEVICEHEIGHTPOINTS=648 \
  -dFIXEDMEDIA -dPDFFitPage \
  input.pdf

This approach re-renders the PDF at the specified dimensions, fitting the content to the new page size. Unlike CropBox-based cropping, this creates a new file with the specified dimensions, removing any content outside the crop area permanently.

Using pdfCropMargins (Python)

The pdfCropMargins Python package provides an excellent command-line tool specifically designed for PDF margin cropping:

# Install
pip install pdfCropMargins

# Auto-crop to content boundaries
pdfCropMargins -p 0 input.pdf

# Crop with uniform margins
pdfCropMargins -p 10 input.pdf  # 10% margin

# Crop specific page range
pdfCropMargins -p 0 -pg 1-10 input.pdf

This tool analyzes each page, detects the content boundaries, and crops to those boundaries with optional margin padding. It is ideal for batch-processing scanned books and documents where margins are inconsistent.

Cropping Specific Page Ranges

Many cropping scenarios require different treatment for different pages. For example:

• Cover pages might need wider margins than body pages
• Landscape pages in a portrait document need different crop dimensions
• Index or bibliography pages might have different layouts than the main content

For splitting and recombining PDFs around crop operations, see our guide on how to merge and split PDFs. The PDF page extractor is also useful for isolating individual pages before cropping.

Common Cropping Scenarios

Removing Scanner Margins

Scanned documents typically have white borders from the scanner bed, sometimes uneven (wider on one side than the other). The most effective approach is auto-detection: tools that analyze the page content and crop to the actual content boundaries.

In Acrobat Pro, use the Remove White Margins option. With command-line tools, pdfCropMargins -p 0 achieves the same result. For online tools, visually drag the crop handles to match the content edges.

If the scanned pages are also slightly rotated (common with handheld scanning), rotate the pages to correct the skew before cropping. Cropping a skewed scan produces uneven margins and wasted space.

Cropping for Screen Reading

Academic papers and books formatted for printing often have 1-inch or wider margins on all sides. On a laptop or tablet screen, these margins waste valuable display area and make the text smaller than necessary. Cropping to tighter margins (0.25 to 0.5 inches) significantly improves the reading experience on digital devices.

Apply a uniform crop to all pages, keeping a small margin for visual comfort. Zero-margin cropping (content touching the edge of the display) looks cramped and makes it harder to hold a tablet without accidentally covering content.

Cropping for Embedding

When embedding a PDF page in a presentation, web page, or another document, you often need to crop to a specific aspect ratio or extract just one element (a chart, a diagram, a single figure).

The process:

1. Extract the specific page from the PDF
2. Crop to the element you need
3. Optionally convert the cropped PDF to an image (JPG or PNG) for easier embedding

For web embedding specifically, converting to an image format after cropping is usually the best approach, since image files are more universally supported in web content than embedded PDFs.

Cropping vs. Resizing vs. Trimming

These terms are related but mean different things in the PDF context:

Cropping changes the visible area by hiding content outside the crop boundaries. The page dimensions change, but the hidden content may still exist in the file (depending on the method used).

Resizing changes the scale of the content to fit different page dimensions. If you resize a letter-size PDF (8.5 x 11 inches) to A4 (8.27 x 11.69 inches), the content is scaled to fit the new dimensions. The PDF resizer handles this type of operation.

Trimming is a print production term. The TrimBox defines where the paper will be cut after printing. Trim marks (small lines at the corners of the page) indicate where the cut should happen. This is different from digital cropping because it describes a physical cutting operation.

Understanding these distinctions helps you choose the right operation for your needs. If you want to remove white space, crop. If you want to change the page size while preserving all content, resize. If you are preparing a document for professional printing, set the TrimBox.

Batch Cropping Large Documents

For documents with hundreds of pages, manual page-by-page cropping is impractical. Batch approaches include:

Uniform Batch Crop

Apply the same crop dimensions to every page in the document. This works well when all pages have the same layout (like a book or report with consistent margins). Most tools, including the online PDF cropper and Acrobat Pro, support applying a crop to all pages simultaneously.

Content-Aware Batch Crop

Auto-detect the content boundaries on each page and crop individually. This handles documents where margins vary from page to page (common in scanned documents). The pdfCropMargins command-line tool excels at this, analyzing each page independently and cropping to the detected content edges.

Scripted Batch Crop

For recurring workflows (like processing daily scanned documents), script the crop operation:

import subprocess

def crop_pdf(input_path, output_path, margins="0"):
    """Auto-crop a PDF to content boundaries."""
    subprocess.run([
        'pdfCropMargins', '-p', margins,
        '-o', output_path, input_path
    ], check=True)

# Process all PDFs in a directory
import os
input_dir = '/path/to/scanned-pdfs/'
output_dir = '/path/to/cropped/'

for filename in os.listdir(input_dir):
    if filename.endswith('.pdf'):
        crop_pdf(
            os.path.join(input_dir, filename),
            os.path.join(output_dir, filename)
        )

Frequently Asked Questions

Does cropping a PDF reduce file size?

Usually no, or only minimally. Standard CropBox-based cropping hides content but does not remove it from the file. The file size remains essentially the same. To actually reduce file size, you need to either modify the MediaBox (permanently removing hidden content) or re-render the PDF. For file size reduction, see our guide on how to reduce PDF file size.

Can I undo a PDF crop?

If the crop only modified the CropBox (which most tools do by default), yes -- any tool that can edit page boxes can restore the original CropBox to match the MediaBox, revealing the hidden content. If the crop modified the MediaBox or re-rendered the PDF, the crop is permanent and the original content is lost.

Can I crop a password-protected PDF?

You need the owner password (the one that controls editing permissions) to crop a protected PDF. The user password (the one needed to open the file) alone is not sufficient for modification. If you have the owner password, enter it when prompted. If you do not, you need to remove the password protection first (which requires the password).

How do I crop all pages to the same size?

In most tools, there is an option to apply the crop to all pages rather than just the current page. In Acrobat Pro, select "All" in the page range when setting page boxes. In online tools, look for an "Apply to all pages" option. From the command line, tools like pdfCropMargins apply to all pages by default.

Can I crop a specific area from the middle of a page?

Yes, but the result is a page containing only that area. Set the CropBox to cover just the region of interest, and the rest of the page content is hidden. This is useful for extracting charts, diagrams, or figures from a larger page.

Wrapping Up

Cropping a PDF is one of those deceptively simple operations that has genuine depth when you look closely. For quick, one-off cropping tasks, the online PDF cropper gets you from upload to download in under a minute. For precise control over page boxes and page ranges, Acrobat Pro provides professional-grade tools. For batch processing scanned documents, command-line tools automate the entire workflow.

The key insight is understanding what cropping actually does -- it changes the visible boundaries of the page, not necessarily the content within the file. For most purposes, this distinction does not matter. But when dealing with sensitive content, large file sizes, or print production, knowing the difference between CropBox and MediaBox operations keeps you out of trouble and ensures your cropped PDFs behave exactly as expected.