How to Convert Color PDF to Black and White: 7 Ways on Windows, Mac, iPhone and Android

If you are wondering how to convert color PDF to black and white, the fastest free route is a browser tool: open LeadCanal’s free convert color PDF to black and white tool, drop the file in, pick Grayscale or Pure black and white, and download the new PDF. The file never leaves your device. If you only want a black and white printout, you do not need to convert anything: choose Grayscale or Black and White in the print dialog. Need selectable text in the new file? Use Adobe Acrobat Pro, Mac Preview or Ghostscript instead.

We built that converter because we handle client PDFs every day, and many must go out in grayscale. Below is every method we use and how to fix the usual problems.

Grayscale vs pure black and white: which one do you need?

Most people say “black and white” when they mean grayscale. The two give very different results, so decide first.

• Grayscale turns every color into a shade of grey. Photos, charts and logos stay readable. This is what most print dialogs and Acrobat produce.
• Pure black and white (also called 1-bit, monochrome or bitonal) makes every pixel either black or white, like a fax or photocopy. Text looks crisp, but photos turn into blotches.

Our rule of thumb: if the PDF has any photo or colored chart, choose grayscale. Use pure black and white only for plain text, or when a form explicitly asks for it.

When do you actually need a black and white PDF?

• Form and portal rules. Some courts, government offices, schools and employers ask for grayscale or black and white scans and attachments.
• Printing. A grayscale file prints the same way on any printer, and you save color ink.
• File size. A scanned color PDF usually gets smaller in grayscale, which helps with email and upload limits.

How to convert color PDF to black and white: 7 methods

Here is how to convert color PDF to black and white on every platform, starting with the method that works on any device.

1. LeadCanal’s free browser converter (any device, no upload)

Our color PDF to black and white converter runs inside your browser. Your computer or phone does the work, so the PDF is never uploaded.

1. Open the tool and drop in your PDF. If it is password protected, you are asked for the password, which stays on your device.
2. Choose Output: Grayscale (keeps shades and photos) or Pure black and white (smallest, crisp text).
3. For pure black and white, set the cut-off from 20 to 240. The default is 170. A higher number keeps more light grey as black.
4. Pick Quality: Draft 100 dpi, Standard 150 dpi, High 200 dpi or Print 300 dpi.
5. Click Convert to black and white and download the file. Page sizes and order stay the same.

One honest limit: the tool rebuilds each page as an image, so text in the new PDF is not selectable or searchable. That is how it guarantees no color survives anywhere in the file. Keep the original if you need to search or copy text later.

2. The print dialog (any app, saves ink, file unchanged)

If you only need paper copies, printing is the simplest answer. The print dialog changes the printout, not the PDF.

1. Open the PDF and press Ctrl+P on Windows or Cmd+P on Mac.
2. Look for a color setting. Depending on the app and printer, it is called Grayscale, Black and White, Monochrome or Color: Black and white. In Adobe Acrobat Reader it is a checkbox, “Print in grayscale (black and white)”.
3. If you cannot see it, open the printer’s Properties, Preferences or More settings panel.
4. Print.

You can sometimes save a grayscale copy by printing to Microsoft Print to PDF. Acrobat Reader’s grayscale checkbox works for this, because Reader converts the pages first. Many other apps ignore the setting, so always check the saved file.

3. Mac Preview with a Quartz Filter (free on macOS)

1. Open the PDF in Preview.
2. Choose File > Export. Keep Format set to PDF.
3. Open the Quartz Filter menu and choose Gray Tone for grayscale or Black & White for a harsher, high-contrast look.
4. Give the file a new name and click Save.

Results vary by file: the Black & White filter can wash out light text, and file size may go up or down. Gray Tone is usually the safer choice. See Apple’s Preview User Guide for more on exporting.

4. Adobe Acrobat Pro: Convert Colors or Preflight (paid, keeps text)

Acrobat Pro converts the colors inside the PDF without turning pages into images, so text stays selectable. Free Acrobat Reader cannot do this; it only offers grayscale printing.

1. Open the PDF in Acrobat Pro.
2. Open the Print Production tools. In the newer Acrobat layout you find them under All tools; in older versions under Tools.
3. Choose Convert Colors.
4. Set the conversion to a grayscale destination profile (for example Gray Gamma 2.2 or a Dot Gain profile), choose the pages, and click OK.
5. Save the file under a new name.

Another route in Pro is Preflight: open the PDF Fixups list and run the “Convert to grayscale” fixup. Adobe’s own guide to making a PDF greyscale walks through the current interface. Menu labels shift between Acrobat releases, so search the tools panel for “Convert Colors” if you do not see it.

5. Ghostscript command line (free, most accurate)

Ghostscript is a free, open-source PDF engine for Windows, Mac and Linux. It rewrites the file in grayscale and keeps text as text, so it is the most accurate free option for long reports and batches.

gs -sDEVICE=pdfwrite -sColorConversionStrategy=Gray -dProcessColorModel=/DeviceGray -dCompatibilityLevel=1.4 -dNOPAUSE -dBATCH -dSAFER -sOutputFile=output-gray.pdf input.pdf

• On Windows the command is gswin64c instead of gs.
• The settings are documented in the Ghostscript pdfwrite documentation.

Ghostscript gives grayscale, not pure 1-bit black and white. For strict monochrome, use a raster option such as our browser tool.

6. iPhone and iPad

• New file: open the browser converter in Safari, tap the upload area, pick the PDF from Files, convert and save the result back to Files. It runs on the phone itself.
• Printout only: open the PDF in Files, tap Share, then Print. If your AirPrint printer supports it, turn on the Black & White option before printing.

7. Android

• New file: open the converter in Chrome, choose the PDF from your files, convert and download.
• Printout only: open the PDF, tap Share or the three-dot menu, then Print. Pick your printer, expand the options and set Color to Black & white where your printer offers it.

Which method should you choose?

Why does it matter that the converter does not upload your PDF?

The PDFs people convert are often private: signed contracts, ID scans, medical letters, tax forms and bank statements. Most online converters upload the file to their server, so a copy of your document sits on someone else’s computer for a while.

Our converter processes the PDF with your own device. The file is never uploaded to LeadCanal or anyone else, and nothing is stored. Close the tab and it is gone. Each tool also checks the file type and its first bytes, so a renamed program is refused before it opens. The same approach powers our bank statement to Excel converter, where privacy matters even more.

A worked example: a color report for a “grayscale only” portal

A typical job: a client must submit a 12-page color report with charts through a portal that only accepts grayscale files under a size limit.

1. We open the color PDF to black and white tool and drop in the report.
2. We choose Grayscale, not pure black and white, because the charts use colored lines that would merge or vanish in 1-bit mode.
3. We set Quality to Standard 150 dpi, which is sharp on screen and fine for office printing.
4. We check a chart page to confirm the legend is still readable.
5. The file is still over the limit, so we run it through compress PDF to 300KB, which lets us pick a target size.

The original color file stays in the client folder for anyone who needs to search the text.

Quality settings and file size: what to pick

A note on file size: a scanned color PDF usually shrinks in grayscale, and pure black and white is smallest for text pages. A PDF made from a word processor works the other way. Its text is stored as tiny instructions, and turning pages into images can make the file bigger. If the result is too large, lower the dpi or compress the file afterwards.

Troubleshooting: common problems and fixes

Most problems people hit when learning how to convert color PDF to black and white come down to one of these.

• Light grey text or highlights disappeared. In pure black and white mode, raise the cut-off so more light grey becomes black, or switch to Grayscale.
• Everything looks too dark or blotchy. Lower the cut-off, or use Grayscale for pages with photos.
• The printout still came out in color. The app setting and the printer driver can disagree. Set black and white in both the print dialog and the printer’s own Properties panel.
• The saved “grayscale” PDF is still in color. Your virtual PDF printer ignored the setting. Use the browser converter, Preview, Acrobat Pro or Ghostscript instead.
• The file got bigger. The original was a text-based PDF. Use a lower dpi, compress it, or use Ghostscript to keep text as text.
• I can no longer select or search the text. That is expected with image-based conversion. Keep the original, or redo it with Acrobat Pro, Preview or Ghostscript.
• Convert Colors is missing in Acrobat. It needs Acrobat Pro. Reader only offers grayscale printing.

What else can you do with the converted PDF?

• Shrink it for an upload limit with our PDF compressor, which targets sizes from 50KB to 2MB and has its own grayscale option.
• Turning phone photos of pages into one PDF first? Use combine JPG to PDF, then convert the result.
• Have an OpenDocument file? Convert it with ODT to PDF before you make it grayscale.
• Browse every converter on our free tools page.

Frequently asked questions

How do I convert a color PDF to black and white for free?

Use a free browser converter such as LeadCanal’s, Mac Preview’s Quartz Filter, or Ghostscript. For printing only, choose Grayscale or Black and White in the print dialog.

Can I convert a color PDF to black and white in Adobe Reader?

Not as a saved file. Acrobat Reader only offers “Print in grayscale” when printing. Converting the file itself needs Acrobat Pro’s Convert Colors or Preflight tools, or another method in this guide.

How do I convert a PDF to black and white, not grayscale?

Use a tool with a true 1-bit option. In our converter, choose Pure black and white and adjust the cut-off until text is crisp and nothing important disappears.

How do I convert a color PDF to black and white on a Mac?

Open it in Preview, choose File > Export, pick the Gray Tone or Black & White Quartz Filter, and save under a new name.

Does converting a PDF to black and white reduce file size?

Often, for scanned PDFs and photo-heavy files. Text-based PDFs can grow when pages become images, so compress afterwards or use Ghostscript.

Can I turn a black and white PDF back into color?

No. The color information is removed during conversion. Always keep the original color file.

How do I print a PDF in black and white on an iPhone?

Open the PDF in Files, tap Share, then Print, and turn on Black & White if your AirPrint printer offers it. For a converted file, use a browser converter in Safari.

What is the safest way to convert color PDF to black and white online?

Use a browser-based converter that processes the file on your device. Upload-based sites keep a copy on their servers for a time, which matters for private documents.

Conclusion: key takeaways

The answer to how to convert color PDF to black and white depends on the result you need: a new file, a printout, or selectable text. Grayscale suits most documents.

• Use grayscale for photos and charts, and pure black and white only for plain text.
• For a free converted file on any device, use a browser converter that does not upload your PDF.
• The print dialog saves ink but leaves the PDF itself in color.
• Use Acrobat Pro, Mac Preview or Ghostscript when text must stay selectable.
• Check the result, and compress it if the black and white file is larger than allowed.
• Always keep the original, because removed color cannot be restored.

Editorial policy

We write our converter guides from hands-on use. Every method was checked against the official documentation, and we describe menu paths generally where they differ between versions. We update guides when tools change and accept no payment for including any software.

Content transparency

This guide was researched with keyword data on what people search for and checked against Adobe, Apple and Ghostscript documentation. LeadCanal offers the free converters mentioned here. They run in your browser, store nothing, and we point out their limits, such as non-selectable text, so you can pick the right method.

About the author

This guide was written by the LeadCanal team. We build verified B2B contact lists, clean CSV and VCF files and handle client PDFs every day, which is why we built free browser converters for the jobs we do most. We test each method on real documents.