How to print a colour PDF in black and white
By the PdfDady team · Updated · 6 min read
If you are printing at home, you usually don't need to change the PDF at all. Open the print dialog, find the colour option, and switch it to black and white or grayscale. The file stays as it is and only the printout loses its colour.
Converting the file itself makes sense in two cases: someone else will print it (a shop, an office, a relative) and you don't want to depend on their settings, or you have been asked to submit a black-and-white file. For that, our Grayscale PDF tool makes a copy with every page in grey or pure black and white, in your browser, without uploading the document.
Option 1: change the printer setting
This is the quickest route and it keeps your PDF untouched.
- Adobe Acrobat Reader: press Ctrl+P and tick the box labelled "Print in grayscale (black and white)" under the printer name.
- Mac: the Print dialog lets you choose between colour and black and white, as long as the printer is a colour one.
- Other apps and printer drivers: look in the print dialog, or under Printer Properties or Preferences, for an option called Black & White, Grayscale or Monochrome. The name depends on the printer maker.
The print preview normally turns grey once the setting is on. If it still shows colour, the setting has not taken effect, so check before you send 40 pages.
Two things catch people out. First, the setting often resets, so the next job prints in colour again unless you make it the default in the printer's own preferences. Second, some apps have their own colour switch and the printer driver has another, and the driver wins. If a page comes out in colour even though you ticked the box, open the printer's properties and set it there too.
Option 2: convert the PDF itself
Do this when the file leaves your hands.
- Open the Grayscale PDF tool and add your PDF (one file, up to 100 MB).
- Choose the look: Grayscale keeps shades of grey, Black & white makes every pixel either black or white.
- Choose the quality: 150 DPI for everyday printing, 300 DPI if the document has small text.
- Check the preview of page 1, then download
grayscale.pdf.
There is one trade-off you should know about before you start. To be sure that every colour is gone, the tool redraws each page as an image. The converted copy looks the same on paper, but you can no longer select, search or copy its text. Keep your original file for anything other than printing.
Grayscale or pure black and white?
They sound alike but behave very differently on a page with photos.
| What is on the page | Better choice | Why |
|---|---|---|
| Photos, ID cards, charts with shading | Grayscale | Shades of grey keep faces and gradients readable |
| Plain typed text, forms, notices | Black & white | Crisper text, and nothing grey to print |
| Coloured highlights or light coloured text | Grayscale | In pure black and white a pale colour can vanish or turn solid black |
| Blue-ink signatures and stamps | Grayscale | They stay visible as dark grey |
If you are not sure, pick Grayscale. It is the safe choice for mixed documents, and the preview shows you roughly how page 1 will look before you download.
A photo of your face on an application form or an Aadhaar copy is the classic case where pure black and white goes wrong: the face becomes a patch of black and white with no detail. Use Grayscale for anything with a photograph.
Check these before you print a long document
Charts that rely on colour. A red line and a green line can turn into two near-identical greys. If the chart matters, look at that page in the converted file and add labels in the original if you can.
Coloured text on a coloured background. White text on a dark blue header is fine. Yellow text on white, or a pale tick mark, may be too faint in grey.
Print one page first. Before a 60-page project report or a set of notes, print a single page with a photo or chart on it. A test page costs almost nothing and tells you whether the grey is dark enough.
At a print shop or cyber café
Black-and-white prints generally cost less per page than colour ones, so it is worth saying clearly which you want. Shop staff handle many jobs in a row and a file that arrives in colour may simply be printed in colour.
A converted file removes the guesswork. A few habits help:
- Convert only the pages that should be black and white. If your cover page needs colour, keep it as a separate file and say so.
- Name the file so the instruction is obvious, for example
report-bw.pdf. - Send the PDF itself, not a screenshot of it. Screenshots print blurry.
- Ask for one page first if the job is large.
If the converted file is too big
Because pages become images, the grayscale copy can be larger than the original, especially at 300 DPI. A text-only PDF of a few hundred KB can grow noticeably.
That does not matter for printing. It does matter if you need to upload the file to a portal with a size limit. Try 150 DPI first. If it is still too large, run the result through Compress PDF, which can aim for a target size such as 200 KB or 1 MB. Open the compressed file and make sure small text is still readable before you upload it.
If your pages started life as phone photos of paper, you may get a cleaner and smaller result by rebuilding them with Scan to PDF, which has a black-and-white document look that turns grey paper and shadows white.
Questions people ask
Does printing in grayscale use no colour ink at all?
It depends on the printer and its driver. If saving colour ink is the whole point, look for an option in the printer's properties that says to use the black cartridge only, and check your printer's manual for what its grayscale mode does.
Can I turn the black-and-white PDF back into colour?
No. The colour information is removed from the converted copy. Your original file is not changed, so keep it.
Why can't I select text in the converted file?
Each page is redrawn as an image so that text, pictures and drawings all lose their colour. An image of text is not selectable. If you need to copy text, use the original PDF.
My portal asks for a black-and-white scan. Is this the same thing?
A converted PDF is a black-and-white file, which is normally what such an instruction is about. Rules differ, so read the notice for any extra conditions such as resolution or file size, and follow those too.
Is the PDF uploaded anywhere?
No. The pages are converted in your browser and the file stays on your device.