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Scan PDF Cleaner

Enhance scanned PDF readability

No upload · 100% in your browser

The scan PDF cleaner raises contrast on faded documents for readable, OCR-friendly results. Adjust brightness and threshold to cut background noise and sharpen characters.

How to use

  1. Upload the scanned PDF.
  2. Adjust brightness for overall tone.
  3. Use threshold to clean background/text contrast.
  4. Generate and download the cleaned PDF.

When it helps

  • Cleaning up faded contract scans
  • Improving readability of receipts and notes
  • Boosting OCR recognition accuracy

Good to know

Too high a threshold can erase thin characters. Adjust gradually using the first-page preview as a guide.

Frequently asked questions

Does it help OCR?

Higher contrast and less noise improve recognition accuracy.

Characters disappear.

Lower the threshold to reduce thin-character loss.

Do color documents work?

Brightness and threshold adjustments clean them for readability.