Skip to main content
Mofumi PDF

Ink Contrast Booster

Beta

Make faded handwriting, pencil notes and old scans dark and readable.

100% Private — files never leave your device
Upload PDFDrop files here or click to chooseAccepted: PDF Files never leave your device

About this tool

Pencil notes, ballpoint on thin paper and decades-old photocopies often scan as pale grey on grey. Ink Contrast Booster renders each page, stretches the tonal range so paper becomes white and ink becomes dark, raises contrast, darkens thin strokes and sharpens edges.

In black-and-white mode the page is also thresholded to pure black and white — automatically with Otsu's method, or at a level you choose. This gives the crispest result for printing, faxing or OCR, and keeps files small.

Pages are converted to images at the resolution you pick; pages outside your selection are kept untouched. The tool is in beta: very uneven lighting may still need a manual threshold.

Engines: pdfjs · canvas · pdf-lib

How to use

  1. 1

    Drop the faded scan.

  2. 2

    Choose Enhance or Black & white and adjust contrast and darkness.

  3. 3

    Click Enhance pages and download the readable PDF.

Use cases

  • Handwritten notes

    Make pencil lecture notes or a notebook scan readable on screen.

  • Old documents

    Revive faded photocopies, carbon copies and thermal-paper receipts.

  • Before OCR

    Clean black-and-white pages recognise much better in OCR PDF.

Frequently asked questions

Will colour be kept?

No, the output is greyscale or black and white — that's what gives faint ink the most contrast.

Which mode should I use?

Enhance keeps soft greys and suits photos and drawings. Black & white is best for text and handwriting.

Is the text still selectable?

Enhanced pages become images. Run OCR PDF afterwards to make them searchable again.

You may also like