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PDF to Grayscale or Black and White

Convert color PDF pages to grayscale or pure black and white in your browser. Prepare files for monochrome printing, archiving and smaller files. Private, no upload.

  • Runs in your browser

    Files are never uploaded — they stay on your device.

  • No page limit

    Any document size, no per-page caps or quotas.

  • No watermarks

    Clean output with no branding added.

  • No sign-up

    Just open the tool and use it — no email, no account.

All processing happens in your browser. Your files are never uploaded.
How to verify

Verify in 3 steps

No promises to take on faith — check it yourself in about 30 seconds.

  1. 1Open DevTools → Network tab
  2. 2Add a file and run the tool
  3. 3Confirm: no request carries your file

Once the page has loaded you can also unplug the network — every tool keeps working.

Full method & limits

Key Features

Grayscale Conversion

Convert colour pages to shades of gray while preserving tonal differences in photos, diagrams and scanned documents.

Pure Black and White

Use a binary black-and-white mode with an adjustable threshold for clean photocopies, OCR preparation and monochrome printing.

Page Preview

Preview the result before export so you can check text clarity, background removal and image detail.

Page Selection

Convert all pages or process only selected pages and page ranges.

Print-Friendly Output

Prepare documents for monochrome printers, copying, archiving and smaller colour-free files. Page size follows the original.

Browser-Based Processing

Convert supported PDF pages directly in your browser without changing the original document.

How to Use

1

Add Your PDF

Drop a colour PDF into the tool. Nothing is uploaded — the file stays on your device.

2

Choose Grayscale or Black and White

Pick Grayscale to keep shades of gray, or Pure Black & White for two-tone output. Adjust the threshold and pick the pages you need.

3

Preview and Download

Compare the original and the converted page, then download the new PDF. Your source file is never overwritten.

PDF to Grayscale Example

A colour report with charts becomes a monochrome PDF ready for black-and-white printing.

PDF
quarterly-report.pdf

A colour report with photos, shaded charts and body text.

PDF
quarterly-report-grayscale.pdf

The same pages in shades of gray, at the original page size and ready for a monochrome printer.

How to Convert a PDF to Grayscale or Black and White

Why Convert to Grayscale or Black and White

Colour is expensive to print and unnecessary for many documents. Removing it prepares a PDF for a monochrome printer, reduces colour-ink usage, creates a consistent archive copy, and can make scanned pages cleaner before OCR.

Grayscale or Pure Black and White?

Grayscale keeps multiple shades between white and black, so it preserves more detail in photographs, scans and shaded graphics. Pure black and white uses only two tones, which can produce cleaner text documents but may remove light lines and subtle image detail. They are not the same thing, and picking the wrong one is the most common reason a converted page looks wrong.

How to Convert a PDF

  1. Add your PDF.
  2. Select Grayscale or Pure Black & White.
  3. Choose all pages or a page range.
  4. Preview the converted pages.
  5. Download the new PDF.

When to Choose Grayscale

  • Scanned documents.
  • Photographs and illustrations.
  • Reports with gray shading.
  • Documents that need readable monochrome printing.

When to Choose Pure Black and White

  • Text-only documents.
  • Photocopying.
  • OCR preparation.
  • Simple line drawings and forms.

Will Text Stay Selectable?

This tool renders each page and rebuilds it, so the output is a visual copy rather than a recoloured original. Text may no longer be selectable or searchable, and links, forms and annotations may not survive. If you rely on those, keep the source PDF and treat the converted file as a print or archive copy.

Why the File Size May Change

Removing colour can reduce file size, but the result depends on the original PDF and the export method. Image-heavy scans may shrink substantially, while already optimised text PDFs may change very little or become larger after reconstruction.

Common Uses

  • Prepare PDFs for black-and-white printing.
  • Reduce colour-ink usage.
  • Create monochrome archive copies.
  • Prepare scans for OCR.
  • Create a consistent grayscale document for sharing.

Related Tools

Frequently Asked Questions

What is the difference between grayscale and pure black and white?

Grayscale keeps many shades between white and black, while pure black and white uses only two tones. Grayscale preserves more image detail; pure black and white is better for simple text, copying, OCR preparation and strict monochrome output.

Can I convert only selected PDF pages?

Yes. Process the whole PDF or enter specific pages and ranges before exporting the new grayscale or black-and-white PDF.

Will the text remain readable?

Text clarity depends on the source PDF, the selected mode, the resolution and the threshold. Preview the result before downloading, especially when converting scanned pages or small text.

Will this reduce printing costs?

Removing colour can reduce colour-ink usage, although the actual savings depend on the printer, the document content and the mode you choose.

Can I convert a scanned PDF?

Yes. Scanned pages are converted as images. Grayscale usually preserves more scan detail, while pure black and white may remove light lines or small details.

Does this preserve selectable text?

No. Pages are re-rendered to apply the colour change, so the output is a visual copy: text may no longer be selectable or searchable, and links, forms or annotations may not survive. Keep the original PDF if you need those.

Will the file get smaller?

It may, especially for colour scans and image-heavy documents. The result depends on the original images, compression, resolution and export method, so a fixed reduction cannot be guaranteed.

Are my PDF files uploaded?

No. The pages are rendered and converted locally in your browser, so no server upload is required and the original file remains unchanged.