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PDF Margin Removal Tool

Remove white margins automatically (scan-enhanced) or manually, and unify the whole document with the same crop box.

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When you need PDF margin removal (crop)

Removing margins reduces white space, makes pages feel fuller, and improves readability for printing/submission.

Scanned PDFs often keep large paper margins; auto cropping can make them look much cleaner.

  • Print documents If content looks too small, reducing margins makes text appear larger.
  • Proof/submission Removing unnecessary margins makes the document look more polished.
  • Cleaning up scans Very effective when scans include large blank areas due to margins/shadows/borders.
Does removing margins reduce file size too?+

Sometimes size may decrease as page dimensions shrink, but image-based scans may still need separate compression (recommended to use with a PDF compression tool).

Auto vs manual crop: which should you use?

Auto (scan-enhanced) works for most PDFs. Text PDFs are fast with GS bbox, and scans are handled more accurately with Raster analysis.

Manual is the most reliable choice when you want consistent trimming or when auto doesn’t behave as expected.

  • Hybrid (recommended) Handles mixed normal+scanned documents cleanly with automatic fallback.
  • Raster Often best when the PDF is mostly scanned (image-based).
  • GS bbox Fast for text/vector PDFs (may be less effective for scans).

Tuning tips when scan auto-crop doesn’t work well

Scans may not have a perfectly white paper background, so the 'white threshold' matters.

Large PDFs can be slow at high rendering scales, so adjusting the max side length (px) can help too.

  • Lower the white threshold If the background is grayish, lowering 245 → 235 can improve margin detection.
  • Increase autoPadding If content gets clipped, increase padding (e.g., 2 → 4) to add breathing room.
  • Sampling step For precision use 2; for speed use 4~6.
Why don’t margins shrink on pages full of photos?+

If the background isn’t white, non-white pixels cover most of the page and are treated as content. Manual crop is often more accurate in that case.

Common/Average crop box: make the whole document the same size

Per-page crop is the tightest, but page sizes may vary slightly from page to page.

Using common/average crop boxes keeps the entire document a uniform size, which looks cleaner for printing/submission.

  • Common (safe) Finds a safe shared box so content won’t be cut off on any page.
  • Average (clean) Unifies based on average margins for a cleaner look (some outlier pages may clip; consider a safety margin).
I’m worried about clipping with the average strategy.+

Increase averageSafety (e.g., 2 → 4) to reduce the risk of clipping.

Apply only to the pages you want with range/odd-even/page list

If you want to leave the cover/appendix as-is and crop only the body, page ranges and odd/even options are useful.

Entering a page list allows even more precise targeting.

  • Range Example: apply only to pages 2~20 (exclude the cover).
  • Odd/Even Helpful for duplex scans where margins differ between sides.
  • Page list Example: 1-3, 8, odd (mixed selection supported).
What if page list and start/end are both set?+

Page list takes priority. Clear the list to use start/end/odd-even settings.