Convert to Grayscale (B&W) - Free Online Browser Tool

Convert coloured PDF pages to real monochrome black & white, on the pages you choose.

Converting to grayscale does not simply drop colour — it measures luminance for each pixel, so colours that look similar convert to similar greys rather than to arbitrary shades. That matters on colour-heavy documents, where a naive conversion turns a pale yellow into a muddy grey that reads as nothing.

This convert to grayscale (b&w) utility runs completely inside your web browser. Your document is opened locally and processed on your own device using JavaScript and WebAssembly, so your file is never uploaded to any server. There is no signup, no watermark and no limit on how many documents you can handle.

  • 100% client-side - files never leave your device
  • Instant processing, no upload wait
  • Works on desktop, tablet and mobile
  • Free forever, no account required

Common next steps: Compress PDF, Eco Ink / Toner Saver, PDF to Greyscale, Invert PDF Colors (Night Mode).

How to Use the Convert to Grayscale (B&W) Tool

Four steps, and the whole thing runs locally on your own device.

  1. Load the colour PDF

    Drop in the document you want to print in black and white.

  2. Choose the conversion approach

    Pick a standard grayscale profile, or a high-contrast option if the original is faint or washed out.

  3. Convert the raster content

    Each page’s colour graphics are re-rendered as true monochrome. Text and vector shapes are adjusted to remain legible.

  4. Download the B&W file

    Save the grayscale PDF — noticeably smaller, and much cheaper to print.

Frequently Asked Questions

Will it be as legible as the colour original?

For most documents, yes, because luminance-based conversion preserves perceived contrast. For very low-contrast colour documents, choose the high-contrast option or the result may look flat.

Does this compress the file as a side effect?

Yes, substantially. Monochrome image data needs far fewer bytes than colour, so file size drops sharply and printing gets cheaper.

Does it touch the text layer?

Text remains vector and selectable. Its colour is adjusted to a legible dark grey or black so it stays visible on the new background.

Can I convert back to colour?

No. Once colour information is discarded it cannot be recovered. Keep your original — the source file is never modified.

Is this the same as Invert PDF Colors?

No. Grayscale removes colour while keeping brightness relationships. Invert produces a light-background document for night reading, which is a different goal.