Auto-Crop PDF

Automatically detect content boundaries in scanned PDFs and remove scanner borders, extra margins, and whitespace for cleaner documents.

100% Private

Instant Processing

Browser-Based

Features

Smart content boundary detection using computer vision

Removes scanner borders and black edges automatically

Adjustable margin padding around detected content

Processes all pages in multi-page PDFs

Preserves content quality with high-resolution rendering

Falls back to original page if no content boundaries detected

No AI credits required

Files encrypted during transfer, auto-deleted after processing

How It Looks

Scanned Page

Cropped Result

How It Works

Upload a scanned PDF with scanner borders or extra margins

The tool analyzes each page to detect content boundaries

Pages are cropped to the content area with optional margin padding

Download the trimmed PDF with clean edges

Common Use Cases

Removing black scanner borders from scanned documents

Trimming excessive margins from scanned book pages

Cleaning up misaligned scan margins across multiple pages

Standardizing page sizes in a batch of scanned documents

Preparing scanned archives for digital storage

Removing whitespace borders before printing

Frequently Asked Questions

How does content detection work?

Each page is rendered as an image and converted to binary (black/white). The tool finds the bounding rectangle of all non-white content, then crops to that area with optional margin padding.

Can I adjust the margin around content?

Yes. Set the margin value (0-100 pixels) to control how much padding is kept around the detected content. The default is 10 pixels.

Does it handle multi-page PDFs?

Yes. Every page is analyzed and cropped individually. Each page may end up with different dimensions depending on its content.

What if no content is detected on a page?

If a page appears to be blank or content cannot be detected, the original page is kept unchanged.

What file size limit applies?

The same file size limit as your subscription plan allows. PDFs can have up to 50 pages.

Does this use AI credits?

No. Auto-Crop uses computer vision processing, not AI. It does not consume any AI credits.

Is my file processed securely?

Your files are processed securely by the PDFSub Engine - an isolated server with no internet access. Files are encrypted during transfer and auto-deleted after processing.

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